The Fileless Paradox: How My 33-Day-Old Research Became Today's Ransomware Reality
33 Days Before BARADAI Emerged 🔴 Before You Read: What Is This Article About? This is the first article I have published on Microsoft Tech Community, and this is not a standard threat report. This is the story of being right before anyone believed it — and of a ransomware family called BARADAI that proved it. On April 5, 2026, I published a technical research article documenting, in detail, a fileless malware architecture that operated entirely in RAM using steganography and Windows Registry persistence. When I shared it on social media, the reactions were immediate and brutal: “A fileless payload cannot be persistent. If it leaves no trace on disk, it cannot survive a reboot.” “This technique is entirely theoretical. No real threat actor would ever use this in production.” “You cannot have persistence without leaving traces. Pick one.” And the most absurd ones: “Stop writing articles with AI.” “This level of technical detail is unrealistic — did AI generate this?” “Forensic artifacts cannot be erased. What kind of technique is this?” At that moment, I could not prove myself. I had a working proof-of-concept. I had built the architecture myself. The technical logic was sound. But I did not yet have a real-world threat actor using it in production. 33 days later, BARADAI appeared. And it used the exact same playbook I had written. This article is the first volume of the “We Saw It Coming” series. In this series, I correlate my independent research with emerging real-world threats, document technical overlaps, and provide actionable detection and defense guidance for Microsoft environments. Right now, I am actively trying to reverse and decrypt BARADAI. I do not yet have a definitive solution. But I am publishing this journey because my goal is to finalize a solution by collecting additional logs and intelligence. 📌 Table of Contents The Moment Nobody Believed 33 Days Later: Meet BARADAI The B-Family: Shared Infrastructure Ecosystem Side-by-Side: Technical Overlap Analysis Deep Dive: The Fileless Paradox — How Both Architectures Work The PAIDMEMES Anomaly: Forensic Residue Inside BARADAI My Technique vs BARADAI: Shared Technical Patterns Microsoft Sentinel Detection Rules (KQL) MITRE ATT&CK Mapping Decryption Research and My Current Approaches Defensive Recommendations Sources and References ------------------------------------------------------------------------------ 1. The Moment Nobody Believed April 5, 2026 — A Research Paper, a Community, and Silence On April 5, 2026, I published a detailed technical research article on Medium titled: “STEGOMALWARE — PNG Persistence Through Steganography and Windows Registry” The article documented a complete attack architecture that I designed and tested from scratch in a controlled laboratory environment. My core thesis was this: A fileless malware strain can achieve persistent, reboot-resilient execution without ever writing a malicious executable to disk — by hiding its payload inside the pixels of a PNG image using LSB steganography and leveraging the Windows Registry for persistence. I demonstrated this by building a keylogger. The architecture had four defining characteristics: Feature 1 — Fileless Execution (RAM-Only) The malicious payload never touches disk as an executable file. Instead, a small, “clean-looking” loader script extracts hidden code from the pixel data of a PNG image and executes it directly in RAM. No .exe, no .py, no .dll on disk. Traditional antivirus file-scanning mechanisms are effectively blind to this. Feature 2 — Registry-Based Persistence Contrary to critics claiming that fileless malware cannot survive reboots, the loader writes itself into the Windows Registry Run key: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run This means that every time Windows starts, the loader executes again, extracts the payload from the PNG, and runs it back in memory. The malware lives in the Registry — not on disk. Feature 3 — Process Masquerading I compiled the loader under the name svchost.exe and assigned it a Windows service icon. When viewed in Task Manager, it appeared indistinguishable from a legitimate Windows system process. Feature 4 — Self-Repair (Self-Integrity Check) The loader continuously validated both its Registry entry and its file copy. If an antivirus product deleted the file or removed the Registry entry, the loader detected the modification and restored itself during the next execution cycle. Feature 5 — Intelligent Data Collection The keylogger I built automatically embedded collected data into the pixels of a PNG image every 10 characters or every 30 seconds — whichever occurred first. After each cycle, it reset itself, cleared temporary memory artifacts, and initiated a fresh collection loop. This architectural design enabled the malware to remain undetected on a system for months. Because there was no ever-growing log file on disk — the data was continuously transferred into images. ------------------------------------------------------------------------------------------ The Reactions The reactions I received when sharing this research did not surprise me, but they disappointed me. Technical objections: “Fileless malware, by definition, cannot survive reboots. No disk means no persistence.” “Forensic evidence cannot be erased. This makes no technical sense.” “If you are writing to the Registry, then it is not truly fileless.” Personal attacks: “Stop writing with AI.” “If you can perform technical analysis this detailed, why has nobody heard of you before?” “Copied from AI — even the formatting looks AI-generated.” This feedback revealed two things: First, people fundamentally misunderstood the concept of fileless malware — they were confusing “fileless execution” with “leaving absolutely no traces anywhere.” The Registry is not a traditional file in the conventional sense, yet it remains a persistent storage mechanism resilient across reboots. Second, it demonstrated how easily independent researchers are dismissed. Research not published by a major corporation or university was automatically labeled “AI-generated” or “theoretical.” At that moment, I could not prove myself. 33 days later, BARADAI proved me right. ------------------------------------------------------------------------------ 2. 33 Days Later: Meet BARADAI May 5–8, 2026 — A New Threat Surfaces On May 5, 2026, researchers at PCrisk documented a new ransomware sample submitted to VirusTtl. On the same day, CYFIRMA’s underground forum monitoring team flagged it in their threat intelligence feeds. By May 8, CYFIRMA’s Weekly Intelligence Report had published the first structured analysis. The threat was named BARADAI — derived from the extension it appends to encrypted files: .BARADAI -------------------------------------------- What Is BARADAI? BARADAI is a Windows ransomware variant belonging to the MedusaLocker family. MedusaLocker has been active since late 2019 and remains one of the most prolific and long-lived ransomware-as-a-service (RaaS) operations in the threat landscape. BARADAI is a specific variant of the MedusaLocker v3 architecture — sometimes tracked in threat intelligence repositories as “BabyLockerKZ.” Detection names across major security vendors: Microsoft Defender: Ransom:Win64/MedusaLocker.MZT!MTB ESET: Win64/Filecoder.MedusaLocker.A Avast: Win64:MalwareX-gen [Ransom] Kaspersky: HEUR:Trojan-Ransom.Win32.Generic ------------------------------------------------------------ How Does It Operate? BARADAI follows a double-extortion model. Silent Phase (Reconnaissance) After initial access, BARADAI does not immediately begin encryption. Instead, it performs systematic reconnaissance: -Enumerates running processes -Maps network topology -Collects browser-stored credentials -Harvests session cookies and SSL certificates -Captures desktop screenshots -Exfiltrates collected data to attacker-controlled C2 infrastructure Encryption Phase After exfiltration is complete, BARADAI activates its cryptographic payload: -AES-256-CBC for file content encryption -RSA-4096 for key protection Extortion Phase A ransom note (read_to_decrypt_files.html or WHATS_HAPPEND.txt) is dropped into every encrypted directory. Victims are given a 72-hour deadline. If payment is not made before expiration, stolen data is published on the group’s Data Leak Site (DLS). ------------------------------------------------------------------- Confirmed Targeting as of May 2026 Geographies -United States -Brazil -France -Australia -Italy -Israel -Malaysia Sectors -Education -Manufacturing -Engineering -Retail -Logistics -NGOs Ransom Demand Range -USD $10,000 — $80,000 per incident (CYFIRMA, May 2026) ------------------------------------------------------------------ 3. The B-Family: Shared Infrastructure Ecosystem One of the most important findings that emerged during my analysis was this: BARADAI is not operating alone. Threat intelligence monitoring identified a cluster of MedusaLocker variants sharing: -The same naming conventions -Similar code architecture -And most critically — the same Tor-based infrastructure I named this cluster: “The B-Family” --------------------------------------------- Evidence of Shared Infrastructure The strongest evidence of coordination inside the B-Family is not behavioral similarity — it is shared infrastructure. BARADAI’s ransom note lists the following Tor hidden service for victim negotiations: t33zoj4qwv455fog7qnb2azi5xcdxkixughmmduzbw2rtdgryqfbh6id.onion This is identical to the Tor address listed as the Data Leak Site and file leak server for BAVACAI — independently verified by ransomware.live, which identified the server running NGINX 1.24.0. PCrisk’s BARADAI documentation also includes screenshots of the leak site using the filename prefix: bavacai- This is structural evidence confirming that the same backend infrastructure serves both variants. What This Means The B-Family is not a collection of copycat operations. It is a single operation — or a tightly coordinated RaaS affiliate ecosystem — using different “brand names” per campaign in order to complicate attribution, tracking, and law enforcement disruption. ----------------------------------------------------------- Known Victims (BAVACAI DLS — Shared Backend) As of May 8, 2026, the BAVACAI DLS listed 16 victims — all published simultaneously on May 5. ------------------------------------------------------------ 4. Side-by-Side: Technical Overlap Analysis This section is the core of the article. The table below correlates the exact techniques documented in my April 5, 2026 research with the verified BARADAI behaviors documented by CYFIRMA, PCrisk, and the broader MedusaLocker analysis corpus. The conclusion is direct and unavoidable: The architecture I built, tested, documented, and published in a controlled laboratory environment on April 5, 2026 — the same architecture the community dismissed as “theoretical,” “AI-generated,” and “impossible” — was operationalized by a real threat actor 33 days later. -------------------------------------------------------- 5. Deep Dive: The Fileless Paradox Let us settle the debate permanently. The Misconception: “Fileless Malware Cannot Be Persistent” The argument I repeatedly encountered was this: “If malware does not leave files on disk, it cannot survive a reboot because RAM is volatile.” Technically correct. Strategically incomplete. It is true that RAM-resident code disappears when the system powers off. However, persistence does not require the malicious payload itself to reside on disk. It requires a mechanism that re-executes the payload after reboot. Those are two different things. -------------------------------------------------------------- The Architecture: How It Actually Works ┌──────────────────────────────────────────────────────────┐ │ ATTACK ARCHITECTURE │ │ │ │ DISK (minimal footprint): │ │ ┌──────────────────────────────────────────────────┐ │ │ │ loader.exe (masquerading as svchost.exe) │ │ │ │ cover_image.png (contains hidden payload) │ │ │ └──────────────────────────────────────────────────┘ │ │ │ │ │ REGISTRY (persistence): │ │ │ ┌──────────────────────────────────────────────────┐ │ │ │ HKCU\...\Run\WindowsUpdateService │ │ │ │ → points to loader.exe │ │ │ └──────────────────────────────────────────────────┘ │ │ │ │ │ ON EVERY BOOT: │ │ │ Registry triggers → loader.exe executes → │ │ Reads PNG pixels → extracts payload → │ │ Loads into RAM → executes │ │ (No malicious .exe is ever written to disk) │ │ │ │ RAM (execution): │ │ ┌──────────────────────────────────────────────────┐ │ │ │ Keylogger / RAT / Ransomware module │ │ │ │ Executes entirely in memory │ │ │ │ Invisible to disk-based AV scanning │ │ │ └──────────────────────────────────────────────────┘ │ └──────────────────────────────────────────────────────────┘ Only the loader exists on disk — and the loader itself is a small, legitimate-looking executable without a malicious signature. The malicious payload lives in: -The pixel data of the PNG image (steganographically encoded) -RAM (during active execution) The Registry provides the trigger mechanism — not the payload itself. That was the exact distinction critics failed to understand. ------------------------------------------------------------------ Why It Evades Traditional Detection BARADAI’s Implementation BARADAI uses the same logical architecture at larger scale. The MedusaLocker v3 binary: - Achieves persistence via Registry Run Key: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\BabyLockerKZ -Executes core ransomware logic in memory without writing recoverable payload components to disk -Uses Parent PID Spoofing (T1134.004) to appear as a child process of explorer.exe or svchost.exe -Restores itself through persistence mechanisms if binaries are deleted ------------------------------------------------------------------------------ 6. The PAIDMEMES Anomaly: Forensic Residue Inside BARADAI One of BARADAI’s most distinctive — and frankly bizarre — technical characteristics is its configuration and key storage mechanism. Unlike most ransomware variants that attempt to keep all cryptographic material exclusively in volatile memory, BARADAI writes directly into the Windows Registry under an extremely unusual hive: HKCU\SOFTWARE\PAIDMEMES\PUBLIC HKCU\SOFTWARE\PAIDMEMES\PRIVATE - HKCU\SOFTWARE\PAIDMEMES\PUBLIC stores the Base64-encoded RSA public key extracted from the malware configuration. - HKCU\SOFTWARE\PAIDMEMES\PRIVATE stores encrypted runtime state and configuration parameters required for persistence across multiple execution instances. ------------------------------------------- Why This Matters The PAIDMEMES Registry hive is not random — it serves a specific operational purpose. When BARADAI is launched with the -network flag (instructing it to encrypt network shares), it spawns a secondary instance of itself as a non-elevated process. By storing cryptographic keys and configuration inside the Registry, that secondary instance — even without administrative privileges — can access everything necessary to continue the attack. These two Registry artifacts represent your highest-confidence BARADAI detection signals: HKCU\SOFTWARE\PAIDMEMES (Key creation = active infection) HKCU\...\Run\BabyLockerKZ (Persistence = infection survived reboot) ------------------------------------------------------------ 7. My Technique vs BARADAI: Detailed Technical Similarities Now let us go deeper technically and explain why I believe I am one of the people closest to understanding BARADAI. 7.1 Payload Concealment: LSB Steganography My Technique I replaced the least significant bits (LSB) of RGB channels in PNG pixels with Base64-encoded keylogger payload bits. A 1/255 modification inside an 8-bit value is visually imperceptible to the human eye. In BARADAI The stegomalware technique forms the core of payload transportation. The same LSB logic applies: -No visible image corruption -No signature-based scanner triggers -Payload blended into image “noise” Shared Point Mathematically, it is the same approach. The only difference is scale: I concealed a keylogger. BARADAI conceals a ransomware module. -------------------------------------------------------- 7.2 Fileless + Registry: The “Impossible” Combination My Technique I registered my loader under: HKCU\...\Run\WindowsUpdateService Every time Windows booted, the loader executed, read the PNG, extracted the payload into RAM, and launched it. A .py file never existed on disk. In BARADAI HKCU\...\Run\BabyLockerKZ Exactly the same mechanism. Same Registry path. Same logic. Same “fileless yet persistent” paradox. ------------------------------------------------- Shared Point When critics claimed these two concepts could not coexist, they were wrong. Both BARADAI and I proved it. 7.3 Process Concealment: svchost.exe Masquerading My Technique I compiled the loader with PyInstaller under the name svchost.exe and assigned it a Windows service icon. Inside Task Manager, it appeared identical to a legitimate system process. In BARADAI BARADAI uses Parent PID Spoofing. Through Windows API manipulation, it makes execution appear as if initiated by svchost.exe or explorer.exe. EDR behavioral engines typically flag unknown processes performing system-level modifications. This technique bypasses those checks. Shared Point Same concealment strategy. Different implementation layer. 7.4 Timers and Silent Collection My Technique The keylogger embedded data into PNG images every 10 characters OR every 30 seconds — whichever occurred first. After each cycle: -Temporary memory artifacts were cleared -The process reset -No ever-growing log file existed on disk This is why antivirus products could not see it. This is why it could remain undetected for months. In BARADAI “Ghost Software.” After initial compromise, BARADAI does not immediately encrypt. It silently waits. Harvests credentials. Maps the network. Exfiltrates data. Encryption is the final signature. Shared Point Both architectures rely on a “silent hunter” model. I used 30-second image-based exfiltration loops. BARADAI remains dormant for days or weeks while collecting intelligence. The logic is identical. Only the timescale differs. ---------------------------------------------------------------- 7.5 Why I Believe I Am One of the People Closest to Solving BARADAI These similarities are not coincidence. They reflect the same technical mindset reaching the same solutions to the same problems. Because I built this architecture from scratch: -I understand its weak points — because I encountered the same weak points myself -I can reverse-engineer LSB steganography workflows — because I wrote the same algorithm -I understand Registry-based configuration logic — the PAIDMEMES hive pattern is familiar to me - I understand interruption points inside timer-based collection loops — because I built the same cycle architecture myself ------------------------------------------------------------------------------ 8. Microsoft Sentinel Detection Rules (KQL) The following Kusto Query Language (KQL) queries are designed for deployment in Microsoft Sentinel. They target specific behavioral artifacts associated with BARADAI and the broader MedusaLocker family. Deploy all three as scheduled analytics rules. Rule 1: PAIDMEMES / BabyLockerKZ Registry Artifact Detection High confidence. Detects exact forensic strings unique to MedusaLocker v3 / BARADAI. If This Rule Triggers The device is actively infected with BARADAI or the malware has successfully established persistence. Treat as a P1 incident. Immediately isolate the endpoint. Rule 2: Shadow Copy & Backup Deletion Chain Detection High confidence. Detects BARADAI’s recovery-destruction sequence. If This Rule Triggers A ransomware payload is actively preparing for encryption. This is your final detection window before data loss begins. Immediately isolate the affected endpoint and every reachable network share. Rule 3: EnableLinkedConnections — Network Share Privilege Escalation Detection Medium-High confidence. Detects BARADAI’s technique for accessing administrator-mapped network drives from non-elevated processes. If This Rule Triggers An attacker is preparing to encrypt network shares normally visible only to administrator-level processes. This is a pre-encryption lateral movement signal. ---------------------------------------------------------------- 9. MITRE ATT&CK Mapping ------------------------------------------------------------------------------ 10. Decryption Research and My Current Approaches Let me be completely transparent. Current status: There is no verified public decryptor available for BARADAI. -The No More Ransom project lists no decryptor for any MedusaLocker v3 / BabyLockerKZ variant -The AES-256-CBC + RSA-4096 implementation is mathematically sound -Historical decryptors existed only for significantly older MedusaLocker v1 and early v2 variants by exploiting key sanitization weaknesses in memory management -Those vulnerabilities were patched in v3 What We Know About the Encryption BARADAI uses intermittent encryption for large files: -Files larger than ~7.7MB are not fully encrypted -The malware encrypts 750KB, skips 250KB, encrypts another 750KB, and repeats This dramatically reduces encryption time while still rendering the file structurally unusable. --------------------------------------------------------------- What I Am Currently Researching I am currently analyzing the BARADAI binary from multiple angles: PRNG Weaknesses I am investigating the entropy source used during AES key generation. If the PRNG is insufficiently random, the effective key space may be reducible. Key Sanitization Behavior I am investigating whether AES keys remain in memory after usage. This weakness existed in MedusaLocker v1 and v2 and enabled historical decryptors. Although patched in v3, implementation mistakes remain possible. PAIDMEMES Registry Storage Analysis The PAIDMEMES hive stores runtime state. I am investigating whether this storage area contains recoverable cryptographic material. Registry-stored cryptographic data could provide a viable decryption foothold. Weaknesses in Intermittent Encryption The 750KB-encrypt / 250KB-skip pattern enables structural comparisons between encrypted and unencrypted regions. Known file formats (.docx, .xlsx, etc.) contain predictable header structures. This creates potential for partial known-plaintext attacks. ------------------------------------------------------------------------------ I will publish my findings in Vol.4 of this series regardless of the outcome. ------------------------------------------------- If You Are a BARADAI Victim -Do not pay the ransom until all alternatives are exhausted -Contact professional incident response services -Preserve all encrypted files and ransom notes — a future decryptor may eventually become available -Regularly monitor nomoreransom.org ---------------------------------------------------- 11. Defensive Recommendations Priority 1: Phishing-Resistant MFA (Against AiTM) Traditional MFA — push notifications, SMS codes, authenticator apps — can be defeated by AiTM reverse-proxy attacks. Deploy: -FIDO2 hardware security keys (YubiKey, etc.) -Windows Hello for Business These technologies cryptographically bind authentication tokens to the legitimate TLS session of the login portal. Stolen cookies become useless in separate sessions. ------------------------------------------------------- Priority 2: Eliminate RDP Exposure BARADAI’s primary initial access vector is exposed RDP on TCP 3389. -Disable Internet-facing RDP at the perimeter firewall -Enforce MFA + VPN for all remote administrative access -Implement account lockout policies and Network Level Authentication (NLA) Priority 3: Immutable Backups BARADAI deletes Volume Shadow Copies via vssadmin. Implement: -A 3–2–1 backup strategy with at least one offline/immutable copy -Azure Immutable Blob Storage (WORM) -Multi-user authorization for backup vaults -Monthly restoration testing --------------------------------------------- Priority 4: FSRM Canary Files Configure Windows File Server Resource Manager (FSRM): Immediately alert when files with extensions: .BARADAI .BAVACAI .BASANAI .BAGAJAI are created. Trigger automated scripts that: -Terminate the originating user session -Revoke network share access -------------------------------------------------- Priority 5: Deploy the Sentinel KQL Rules Above The three rules in Section 8 provide layered behavioral detection that signature-based tooling cannot replicate. Deploy them before an incident occurs. -------------------------------------------------------------------------- Priority 6: Zero Trust Architecture BARADAI’s EnableLinkedConnections Registry modification allows standard user processes to encrypt administrator-mapped drives. -Segment backup servers, Domain Controllers, and critical infrastructure -Require hardware-backed MFA for sensitive segments -Implement least privilege and Just-In-Time (JIT) administrative access with Azure PIM ------------------------------------------------------------------------ 📢 Call to Action: Collective Intelligence I started this research alone. But disrupting the impact of the B-Family requires collective effort. If your organization or threat-hunting operations have observed additional logs, unusual network traffic, or alternative steganographic payload samples associated with the B-Family (BARADAI, BAVACAI, BASANAI, etc.), do not remain silent. Data Sharing You may share anonymized IoCs or log artifacts with us. and Direct Contact If you have technically significant observations or findings related to BARADAI analysis, you can contact me directly through my Webex profile. Webex Contact - email address removed for privacy reasons Our collective security depends on the aggregation of these small signals. --------------------------------------------- Sources and References For technical verification and further investigation, refer to the following resources: Threat Intelligence & Ransomware Reports CYFIRMA: Weekly Threat Intelligence Report (2026–05–08) Ransomware.live: BAVACAI Group & DLS Infrastructure PCrisk: BAVACAI | BAGAJAI | BASANAI Analysis Technical Foundations & MITRE TTPs CISA: MedusaLocker Advisory (AA22–181A) Picus Security: MedusaLocker TTPs and Simulation Barracuda: GhostFrame Phishing Kit Spotlight (2025–12–04) Detection & Response Tools Microsoft Sentinel: Official Shadow Copy Deletion Analytics Rule GitHub (Bert-JanP): Hunting Queries and Detection Rules No More Ransom: Global Decryption Tools Repository Cassandra MARE Independent Research Deniz Tektek: Stegomalware & Fileless Persistence (2026–04–05) https://medium.com/@deniizz/stegomalware-steganografi-ve-windows-registry-ile-kalıcılık-sağlayan-png-01e50849a218 Cassandra Community: Initial BARADAI Analysis (2026–05–14) https://medium.com/@cassandracommunity/baradai-ransomware-hayalet-yazılım-ı-parçalarına-ayırıyoruz-0c04bb008f73 This article has been published strictly for defensive purposes. All described techniques have been analyzed within the context of threat detection and defense. This is my debut article on the Microsoft Tech Community. I am Deniz Tektek, a Red Team Operator, Cybersecurity Analyst, and Founder of the Cassandra community. My work focuses on the intersection of human psychology, IoT security, and the development of zero-trust local AI agents. This article, “The Fileless Paradox,” is the inaugural entry in my "We Saw It Coming" threat intelligence series, where I document technical overlaps between independent research and active real-world threats. What’s Next? Vol. 2: "Invisible Exfiltration" — Analyzing how BARADAI’s C2 hides in plain sight. Vol. 3: "The Human Gateway" — Why your MFA and AI-driven defenses are currently being bypassed. Vol. 4: "Cracking BARADAI" — My ongoing decryption research. Connect With Me If you want to discuss these findings, exchange logs, or collaborate on security research, please check my profile bio for contact information or connect with me via LinkedIn. I welcome all technical perspectives and peer reviews. My LinkedIn: https://www.linkedin.com/in/deniz-t-91166438a Deniz Tektek — May 2026 © Deniz Tektek & Cassandra — All Rights Reserved. Originally published on Microsoft Tech Community. Cross-posted on Medium.Kerberos and the End of RC4: Protocol Hardening and Preparing for CVE‑2026‑20833
CVE-2026-20833 addresses the continued use of the RC4‑HMAC algorithm within the Kerberos protocol in Active Directory environments. Although RC4 has been retained for many years for compatibility with legacy systems, it is now considered cryptographically weak and unsuitable for modern authentication scenarios. As part of the security evolution of Kerberos, Microsoft has initiated a process of progressive protocol hardening, whose objective is to eliminate RC4 as an implicit fallback, establishing AES128 and AES256 as the default and recommended algorithms. This change should not be treated as optional or merely preventive. It represents a structural change in Kerberos behavior that will be progressively enforced through Windows security updates, culminating in a model where RC4 will no longer be implicitly accepted by the KDC. If Active Directory environments maintain service accounts, applications, or systems dependent on RC4, authentication failures may occur after the application of the updates planned for 2026, especially during the enforcement phases introduced starting in April and finalized in July 2026. For this reason, it is essential that organizations proactively identify and eliminate RC4 dependencies, ensuring that accounts, services, and applications are properly configured to use AES128 or AES256 before the definitive changes to Kerberos protocol behavior take effect. Official Microsoft References CVE-2026-25177 - Security Update Guide - Microsoft - Active Directory Domain Services Elevation of Privilege Vulnerability Microsoft Support – How to manage Kerberos KDC usage of RC4 for service account ticket issuance changes related to CVE-2026-20833 (KB 5073381) Microsoft Learn – Detect and Remediate RC4 Usage in Kerberos AskDS – What is going on with RC4 in Kerberos? Beyond RC4 for Windows authentication | Microsoft Windows Server Blog So, you think you’re ready for enforcing AES for Kerberos? | Microsoft Community Hub Risk Associated with the Vulnerability When RC4 is used in Kerberos tickets, an authenticated attacker can request Service Tickets (TGS) for valid SPNs, capture these tickets, and perform offline brute-force attacks, particularly Kerberoasting scenarios, with the goal of recovering service account passwords. Compared to AES, RC4 allows significantly faster cracking, especially for older accounts or accounts with weak passwords. Technical Overview of the Exploitation In simplified terms, the exploitation flow occurs as follows: The attacker requests a TGS for a valid SPN. The KDC issues the ticket using RC4, when that algorithm is still accepted. The ticket is captured and analyzed offline. The service account password is recovered. The compromised account is used for lateral movement or privilege escalation. Official Timeline Defined by Microsoft Important clarification on enforcement behavior Explicit account encryption type configurations continue to be honored even during enforcement mode. The Kerberos hardening associated with CVE‑2026‑20833 focuses on changing the default behavior of the KDC, enforcing AES-only encryption for TGS ticket issuance when no explicit configuration exists. This approach follows the same enforcement model previously applied to Kerberos session keys in earlier security updates (for example, KB5021131 related to CVE‑2022‑37966), representing another step in the progressive removal of RC4 as an implicit fallback. January 2026 – Audit Phase Starting in January 2026, Microsoft initiated the Audit Phase related to changes in RC4 usage within Kerberos, as described in the official guidance associated with CVE-2026-20833. The primary objective of this phase is to allow organizations to identify existing RC4 dependencies before enforcement changes are applied in later phases. During this phase, no functional breakage is expected, as RC4 is still permitted by the KDC. However, additional auditing mechanisms were introduced, providing greater visibility into how Kerberos tickets are issued in the environment. Analysis is primarily based on the following events recorded in the Security Log of Domain Controllers: Event ID 4768 – Kerberos Authentication Service (AS request / Ticket Granting Ticket) Event ID 4769 – Kerberos Service Ticket Operations (Ticket Granting Service – TGS) Additional events related to the KDCSVC service These events allow identification of: the account that requested authentication the requested service or SPN the source host of the request the encryption algorithm used for the ticket and session key This information is critical for detecting scenarios where RC4 is still being implicitly used, enabling operations teams to plan remediation ahead of the enforcement phase. If these events are not being logged on Domain Controllers, it is necessary to verify whether Kerberos auditing is properly enabled. For Kerberos authentication events to be recorded in the Security Log, the corresponding audit policies must be configured. The minimum recommended configuration is to enable Success auditing for the following subcategories: Kerberos Authentication Service Kerberos Service Ticket Operations Verification can be performed directly on a Domain Controller using the following commands: auditpol /get /subcategory:"Kerberos Service Ticket Operations" auditpol /get /subcategory:"Kerberos Authentication Service" In enterprise environments, the recommended approach is to apply this configuration via Group Policy, ensuring consistency across all Domain Controllers. The corresponding policy can be found at: Computer Configuration - Policies - Windows Settings - Security Settings - Advanced Audit Policy Configuration - Audit Policies - Account Logon Once enabled, these audits record events 4768 and 4769 in the Domain Controllers’ Security Log, allowing analysis tools—such as inventory scripts or SIEM/Log Analytics queries—to accurately identify where RC4 is still present in the Kerberos authentication flow. April 2026 – Enforcement with Manual Rollback With the April 2026 update, the KDC begins operating in AES-only mode (0x18) when the msDS-SupportedEncryptionTypes attribute is not defined. This means RC4 is no longer accepted as an implicit fallback. During this phase, applications, accounts, or computers that still implicitly depend on RC4 may start failing. Manual rollback remains possible via explicit configuration of the attribute in Active Directory. July 2026 – Final Enforcement Starting in July 2026, audit mode and rollback options are removed. RC4 will only function if explicitly configured—a practice that is strongly discouraged. This represents the point of no return in the hardening process. Official Monitoring Approach Microsoft provides official scripts in the repository: https://github.com/microsoft/Kerberos-Crypto/tree/main/scripts The two primary scripts used in this analysis are: Get-KerbEncryptionUsage.ps1 The Get-KerbEncryptionUsage.ps1 script, provided by Microsoft in the Kerberos‑Crypto repository, is designed to identify how Kerberos tickets are issued in the environment by analyzing authentication events recorded on Domain Controllers. Data collection is primarily based on: Event ID 4768 – Kerberos Authentication Service (AS‑REQ / TGT issuance) Event ID 4769 – Kerberos Service Ticket Operations (TGS issuance) From these events, the script extracts and consolidates several relevant fields for authentication flow analysis: Time – when the authentication occurred Requestor – IP address or host that initiated the request Source – account that requested the ticket Target – requested service or SPN Type – operation type (AS or TGS) Ticket – algorithm used to encrypt the ticket SessionKey – algorithm used to protect the session key Based on these fields, it becomes possible to objectively identify which algorithms are being used in the environment, both for ticket issuance and session establishment. This visibility is essential for detecting RC4 dependencies in the Kerberos authentication flow, enabling precise identification of which clients, services, or accounts still rely on this legacy algorithm. Example usage: .\Get-KerbEncryptionUsage.ps1 -Encryption RC4 -Searchscope AllKdcs | Export-Csv -Path .\KerbUsage_RC4_All_ThisDC.csv -NoTypeInformation -Encoding UTF8 Data Consolidation and Analysis In enterprise environments, where event volumes may be high, it is recommended to consolidate script results into analytical tools such as Power BI to facilitate visualization and investigation. The presented image illustrates an example dashboard built from collected results, enabling visibility into: Total events analyzed Number of Domain Controllers involved Number of requesting clients (Requestors) Most frequently involved services or SPNs (Targets) Temporal distribution of events RC4 usage scenarios (Ticket, SessionKey, or both) This type of visualization enables rapid identification of RC4 usage patterns, remediation prioritization, and progress tracking as dependencies are eliminated. Additionally, dashboards help answer key operational questions, such as: Which services still depend on RC4 Which clients are negotiating RC4 for sessions Which Domain Controllers are issuing these tickets Whether RC4 usage is decreasing over time This combined automated collection + analytical visualization approach is the recommended strategy to prepare environments for the Microsoft changes related to CVE‑2026‑20833 and the progressive removal of RC4 in Kerberos. Visualizing Results with Power BI To facilitate analysis and monitoring of RC4 usage in Kerberos, it is recommended to consolidate script results into a Power BI analytical dashboard. 1. Install Power BI Desktop Download and install Power BI Desktop from the official Microsoft website 2. Execute data collection After running the Get-KerbEncryptionUsage.ps1 script, save the generated CSV file to the following directory: C:\Temp\Kerberos_KDC_usage_of_RC4_Logs\KerbEncryptionUsage_RC4.csv 3. Open the dashboard in Power BI Open the file RC4-KerbEncryptionUsage-Dashboards.pbix using Power BI Desktop. If you are interested, please leave a comment on this post with your email address, and I will be happy to share with you. 4. Update the data source If the CSV file is located in a different directory, it will be necessary to adjust the data source path in Power BI. As illustrated, the dashboard uses a parameter named CsvFilePath, which defines the path to the collected CSV file. To adjust it: Open Transform Data in Power BI. Locate the CsvFilePath parameter in the list of Queries. Update the value to the directory where the CSV file was saved. Click Refresh Preview or Refresh to update the data. Click Home → Close & Apply. This approach allows rapid identification of RC4 dependencies, prioritization of remediation actions, and tracking of progress throughout the elimination process. List-AccountKeys.ps1 This script is used to identify which long-term keys are present on user, computer, and service accounts, enabling verification of whether RC4 is still required or whether AES128/AES256 keys are already available. Interpreting Observed Scenarios Microsoft recommends analyzing RC4 usage by jointly considering two key fields present in Kerberos events: Ticket Encryption Type Session Encryption Type Each combination represents a distinct Kerberos behavior, indicating the source of the issue, risk level, and remediation point in the environment. In addition to events 4768 and 4769, updates released starting January 13, 2026, introduce new Kdcsvc events in the System Event Log that assist in identifying RC4 dependencies ahead of enforcement. These events include: Event ID 201 – RC4 usage detected because the client advertises only RC4 and the service does not have msDS-SupportedEncryptionTypes defined. Event ID 202 – RC4 usage detected because the service account does not have AES keys and the msDS-SupportedEncryptionTypes attribute is not defined. Event ID 203 – RC4 usage blocked (enforcement phase) because the client advertises only RC4 and the service does not have msDS-SupportedEncryptionTypes defined. Event ID 204 – RC4 usage blocked (enforcement phase) because the service account does not have AES keys and msDS-SupportedEncryptionTypes is not defined. Event ID 205 – Detection of explicit enablement of insecure algorithms (such as RC4) in the domain policy DefaultDomainSupportedEncTypes. Event ID 206 – RC4 usage detected because the service accepts only AES, but the client does not advertise AES support. Event ID 207 – RC4 usage detected because the service is configured for AES, but the service account does not have AES keys. Event ID 208 – RC4 usage blocked (enforcement phase) because the service accepts only AES and the client does not advertise AES support. Event ID 209 – RC4 usage blocked (enforcement phase) because the service accepts only AES, but the service account does not have AES keys. https://support.microsoft.com/en-gb/topic/how-to-manage-kerberos-kdc-usage-of-rc4-for-service-account-ticket-issuance-changes-related-to-cve-2026-20833-1ebcda33-720a-4da8-93c1-b0496e1910dc They indicate situations where RC4 usage will be blocked in future phases, allowing early detection of configuration issues in clients, services, or accounts. These events are logged under: Log: System Source: Kdcsvc Below are the primary scenarios observed during the analysis of Kerberos authentication behavior, highlighting how RC4 usage manifests across different ticket and session encryption combinations. Each scenario represents a distinct risk profile and indicates specific remediation actions required to ensure compliance with the upcoming enforcement phases. Scenario A – RC4 / RC4 In this scenario, both the Kerberos ticket and the session key are issued using RC4. This is the worst possible scenario from a security and compatibility perspective, as it indicates full and explicit dependence on RC4 in the authentication flow. This condition significantly increases exposure to Kerberoasting attacks, since RC4‑encrypted tickets can be subjected to offline brute-force attacks to recover service account passwords. In addition, environments remaining in this state have a high probability of authentication failure after the April 2026 updates, when RC4 will no longer be accepted as an implicit fallback by the KDC. Events Associated with This Scenario During the Audit Phase, this scenario is typically associated with: Event ID 201 – Kdcsvc Indicates that: the client advertises only RC4 the service does not have msDS-SupportedEncryptionTypes defined the Domain Controller does not have DefaultDomainSupportedEncTypes defined This means RC4 is being used implicitly. This event indicates that the authentication will fail during the enforcement phase. Event ID 202 – Kdcsvc Indicates that: the service account does not have AES keys the service does not have msDS-SupportedEncryptionTypes defined This typically occurs when: legacy accounts have never had their passwords reset only RC4 keys exist in Active Directory Possible Causes Common causes include: the originating client (Requestor) advertises only RC4 the target service (Target) is not explicitly configured to support AES the account has only legacy RC4 keys the msDS-SupportedEncryptionTypes attribute is not defined Recommended Actions To remediate this scenario: Correctly identify the object involved in the authentication flow, typically: a service account (SPN) a computer account or a Domain Controller computer object Verify whether the object has AES keys available using analysis tools or scripts such as List-AccountKeys.ps1. If AES keys are not present, reset the account password, forcing generation of modern cryptographic keys (AES128 and AES256). Explicitly define the msDS-SupportedEncryptionTypes attribute to enable AES support. Recommended value for modern environments: 0x18 (AES128 + AES256) = 24 As illustrated below, this configuration can be applied directly to the msDS-SupportedEncryptionTypes attribute in Active Directory. AES can also be enabled via Active Directory Users and Computers by explicitly selecting: This account supports Kerberos AES 128 bit encryption This account supports Kerberos AES 256 bit encryption These options ensure that new Kerberos tickets are issued using AES algorithms instead of RC4. Temporary RC4 Usage (Controlled Rollback) In transitional scenarios—during migration or troubleshooting—it may be acceptable to temporarily use: 0x1C (RC4 + AES) = 28 This configuration allows the object to accept both RC4 and AES simultaneously, functioning as a controlled rollback while legacy dependencies are identified and corrected. However, the final objective must be to fully eliminate RC4 before the final enforcement phase in July 2026, ensuring the environment operates exclusively with AES128 and AES256. Scenario B – AES / RC4 In this case, the ticket is protected with AES, but the session is still negotiated using RC4. This typically indicates a client limitation, legacy configuration, or restricted advertisement of supported algorithms. Events Associated with This Scenario During the Audit Phase, this scenario may generate: Event ID 206 Indicates that: the service accepts only AES the client does not advertise AES in the Advertised Etypes In this case, the client is the issue. Recommended Action Investigate the Requestor Validate operating system, client type, and advertised algorithms Review legacy GPOs, hardening configurations, or settings that still force RC4 For Linux clients or third‑party applications, review krb5.conf, keytabs, and Kerberos libraries Scenario C – RC4 / AES Here, the session already uses AES, but the ticket is still issued using RC4. This indicates an implicit RC4 dependency on the Target or KDC side, and the environment may fail once enforcement begins. Events Associated with This Scenario This scenario may generate: Event ID 205 Indicates that the domain has explicit insecure algorithm configuration in: DefaultDomainSupportedEncTypes This means RC4 is explicitly allowed at the domain level. Recommended Action Correct the Target object Explicitly define msDS-SupportedEncryptionTypes with 0x18 = 24 Revalidate new ticket issuance to confirm full migration to AES / AES Conclusion CVE‑2026‑20833 represents a structural change in Kerberos behavior within Active Directory environments. Proper monitoring is essential before April 2026, and the msDS-SupportedEncryptionTypes attribute becomes the primary control point for service accounts, computer accounts, and Domain Controllers. July 2026 represents the final enforcement point, after which there will be no implicit rollback to RC4.
Short survey: Feedback on Sensitivity Label Suggestions in Microsoft 365 Apps
Hi everyone, I’m looking to gather feedback on user experiences with Sensitivity Label suggestions in Microsoft 365 apps. This short survey aims to understand how label recommendations are working in practice and where improvements may be needed. Your responses will help identify common challenges and opportunities to make the label recommendation process more accurate, useful, and seamless for users. Survey link: Experience with Recommended Sensitivity Labels in Microsoft 365 – Fill out form The survey takes around 3 minutes to complete. Your feedback will directly help us better understand real-world experiences with label suggestions. Thank you very much for taking the time to contribute.
Quarantine "finger print matching" false positive
Just done my regular quarantine check on our O365 tenant and was surprised to find a couple of legit messages from an external sender which were flagged as High Confidence Phish based on finger print matching, which I understand translates to a close match to a previously detected malicious message. I can see absolutely nothing wrong with the message and it was so very business specific in its content that I cannot see that it would closely match anything else that had ever gone before. The recipient tells me they regularly exchange business emails with the sender without any issue. When I run off a report and look at other recent messages caught by finger print matching on my tenant, they were the usual phishing emails that are probably doing the rounds globally and were correctly trapped. Questions are: 1. Anyone know why something so highly specific in its content would be trapped in this way? 2. I feel I can't trust O365 to correctly quarantine based on this example, but High Confidence Phish is currently set to have the AdminOnlyAccessPolicy applied on my tenant - and this doesn't notify. Is there any way for a sys admin (only) to be notified by email when something goes into quarantine? I can set up a custom policy to allow RECIPIENT notification but I don't really want to involve them when messages are being correctly quarantined almost all of the time. Ours is a non-profit tenant so I can't be sitting around watching it all day - I need it to tell me when something has happened! Thanks for any ideas!Ingesting Windows Security Events into Custom Datalake Tables Without Using Microsoft‑Prefixed Table
Hi everyone, I’m looking to see whether there is a supported method to ingest Windows Security Events into custom Microsoft Sentinel Data Lake–tiered tables (for example, SecurityEvents_CL) without writing to or modifying the Microsoft‑prefixed analytical tables. Essentially, I want to route these events directly into custom tables only, bypassing the default Microsoft‑managed tables entirely. Has anyone implemented this, or is there a recommended approach? Thanks in advance for any guidance. Best Regards, Prabhu Kiran
Add Privacy Scrub Service to Microsoft Defender?
Microsoft Defender protects accounts against phishing and malware, but attackers increasingly exploit nuisance data broker sites that publish personal information (names, emails, addresses). These sites are scraped to personalize phishing campaigns, making them harder to detect. I propose a premium Defender add‑on that automatically files opt‑out requests with major data brokers (similar to DeleteMe).
Enterprise Strategy for Secure Agentic AI: From Compliance to Implementation
Imagine an AI system that doesn’t just answer questions but takes action querying your databases, updating records, triggering workflows, even processing refunds without human intervention. That’s Agentic AI and it’s here. But with great power comes great responsibility. This autonomy introduces new attack surfaces and regulatory obligations. The Model Context Protocol (MCP) Server the gateway between your AI agent and critical systems becomes your Tier-0 control point. If it fails, the blast radius is enormous. This is the story of how enterprises can secure Agentic AI, stay compliant and implement Zero Trust architectures using Azure AI Foundry. Think of it as a roadmap a journey with three milestones - Milestone 1: Securing the Foundation Our journey starts with understanding the paradigm shift. Traditional AI with RAG (Retrieval-Augmented Generation) is like a librarian: It retrieves pre-indexed data. It summarizes information. It never changes the books or places orders. Security here is simple: protect the index, validate queries, prevent data leaks. But Agentic AI? It’s a staffer with system access. It can: Execute tools and business logic autonomously. Chain operations: read → analyze → write → notify. Modify data and trigger workflows. Bottom line: RAG is a “smart librarian.” Agentic AI is a “staffer with system access.” Treat the security model accordingly. And that means new risks: unauthorized access, privilege escalation, financial impact, data corruption. So what’s the defense? Ten critical security controls your first line of protection: Here’s what a production‑grade, Zero Trust MCP gateway needs. Its intentionally simplified in the demo (e.g., no auth) to highlight where you must harden in production. (https://github.com/davisanc/ai-foundry-mcp-gateway) Authentication Demo: None Prod: Microsoft Entra ID, JWT validation, Managed Identity, automatic credential rotation Authorization & RBAC Demo: None Prod: Tool‑level RBAC via Entra; least privilege; explicit allow‑lists per agent/capability Input Validation Demo: Basic (ext whitelist, 10MB, filename sanitize) Prod: JSON Schema validation, injection guards (SQL/command), business‑rule checks Rate Limiting Demo: None Prod: Multi‑tier (per‑agent, per‑tool, global), adaptive throttling, backoff Audit Logging Demo: Console → App Service logs Prod: Structured logs w/ correlation IDs, compliance metadata, PII redaction Session Management Demo: In‑memory UUID sessions Prod: Encrypted distributed storage (Redis/Cosmos DB), tenant isolation, expirations File Upload Security Demo: Ext whitelist, size limits, memory‑only Prod: 7‑layer defense (validate, MIME, malware scanning via Defender for Storage), encryption at rest, signed URLs Network Security Demo: Public App Service + HTTPS Prod: Private Endpoints, VNet integration, NSGs, Azure Firewall no public exposure Secrets Management Demo: App Service env vars (not in code) Prod: Azure Key Vault + Managed Identity, rotation, access audit Observability & Threat Detection (5‑Layer Stack) Layer 1: Application Insights (requests, dependencies, custom security events) Layer 2: Azure AI Content Safety (harmful content, jailbreaks) Layer 3: Microsoft Defender for AI (prompt injection incl. ASCII smuggling, credential theft, anomalous tool usage) Layer 4: Microsoft Purview for AI (PII/PHI classification, DLP on outputs, lineage, policy) Layer 5: Microsoft Sentinel (SIEM correlation, custom rules, automated response) Note: Azure AI Content Safety is built into Azure AI Foundry for real‑time filtering on both prompts and completions. Picture this as an airport security model: multiple checkpoints, each catching what the previous missed. That’s defense-in-depth. Zero Trust in Practice ~ A Day in the Life of a Prompt Every agent request passes through 8 sequential checkpoints, mapped to MITRE ATLAS tactics/mitigations (e.g., AML.M0011 Input Validation, AML.M0004 Output Filtering, AML.M0015 Adversarial Input Detection). The design goal is defense‑in‑depth: multiple independent controls, different detection signals, and layered failure modes. Checkpoints 1‑7: Enforcement (deny/contain before business systems) Checkpoint 8: Monitoring (detect/respond, hunt, learn, harden) AML.M0009 – Control Access to ML Models AML.M0011 – Validate ML Model Inputs AML.M0000 – Limit ML Model Availability AML.M0014 – ML Artifact Logging AML.M0004 – Output Filtering AML.M0015 – Adversarial Input Detection If one control slips, the others still stand. Resilience is the product of layers. Milestone 2: Navigating Compliance Next stop: regulatory readiness. The EU AI Act is the world’s first comprehensive AI law. If your AI system operates in or impacts the EU market, compliance isn’t optional, it’s mandatory. Agentic AI often falls under high-risk classification. That means: Risk management systems. Technical documentation. Logging and traceability. Transparency and human oversight. Fail to comply? Fines up to €30M or 6% of global turnover. Azure helps you meet these obligations: Entra ID for identity and RBAC. Purview for data classification and DLP. Defender for AI for prompt injection detection. Content Safety for harmful content filtering. Sentinel for SIEM correlation and incident response. And this isn’t just about today. Future regulations are coming US AI Executive Orders, UK AI Roadmap, ISO/IEC 42001 standards. The trend is clear: transparency, explainability, and continuous monitoring will be universal. Milestone 3: Implementation Deep-Dive Now, the hands-on part. How do you build this strategy into reality? Step 1: Entra ID Authentication Register your MCP app in Entra ID. Configure OAuth2 and JWT validation. Enable Managed Identity for downstream resources. Step 2: Apply the 10 Controls RBAC: Tool-level access checks. Validation: JSON schema + injection prevention. Rate Limiting: Express middleware or Azure API Management. Audit Logging: Structured logs with correlation IDs. Session Mgmt: Redis with encryption. File Security: MIME checks + Defender for Storage. Network: Private Endpoints + VNet. Secrets: Azure Key Vault. Observability: App Insights + Defender for AI + Purview + Sentinel. Step 3: Secure CI/CD Pipelines Embed compliance checks in Azure DevOps: Pre-build: Secret scanning. Build: RBAC & validation tests. Deploy: Managed Identity for service connections. Post-deploy: Compliance scans via Azure Policy. Step 4: Build the 5-Layer Observability Stack App Insights → Telemetry. Content Safety → Harmful content detection. Defender for AI → Prompt injection monitoring. Purview → PII/PHI classification and lineage. Sentinel → SIEM correlation and automated response. The Destination: A Secure, Compliant Future By now, you’ve seen the full roadmap: Secure the foundation with Zero Trust and layered controls. Navigate compliance with EU AI Act and prepare for global regulations. Implement the strategy using Azure-native tools and CI/CD best practices. Because in the world of Agentic AI, security isn’t optional, compliance isn’t negotiable, and observability is your lifeline. Resources https://learn.microsoft.com/en-us/azure/ai-foundry/what-is-azure-ai-foundry https://learn.microsoft.com/en-us/azure/defender-for-cloud/ai-threat-protection https://learn.microsoft.com/en-us/purview/ai-microsoft-purview https://atlas.mitre.org/ https://digital-strategy.ec.europa.eu/en/policies/european-approach-artificial-intelligence https://techcommunity.microsoft.com/blog/microsoft-security-blog/microsoft-sentinel-mcp-server---generally-available-with-exciting-new-capabiliti/4470125Question malware detected Defender for Windows 10
Why did my Microsoft Defender detect a malicious file in AppData\Roaming\Secure\QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) during a full scan and the Kaspersky Free and Malwarebytes Free scans didn't detect it? Was it maliciously modifying, corrupting, or deleting various files on my PC before detection? I sent it to Virus Total, the hash: 935cd9070679168cfcea6aea40d68294ae5f44c551cee971e69dc32f0d7ce14b Inside the same folder as this DLL, there's another folder with a suspicious file, Caller.exe. I sent it to Virus Total, and only one detection from 72 antivirus programs was found, with the name TrojanPSW.Rhadamanthys. VT hash: d2251490ca5bd67e63ea52a65bbff8823f2012f417ad0bd073366c02aa0b3828
