Missing details in Azure Activity Logs – MICROSOFT.SECURITYINSIGHTS/ENTITIES/ACTION
The Azure Activity Logs are crucial for tracking access and actions within Sentinel. However, I’m encountering a significant lack of documentation and clarity regarding some specific operation types. Resources consulted: https://learn.microsoft.com/en-us/azure/sentinel/audit-sentinel-data https://learn.microsoft.com/en-us/rest/api/securityinsights/entities?view=rest-securityinsights-2024-01-01-preview https://learn.microsoft.com/en-us/rest/api/securityinsights/operations/list?view=rest-securityinsights-2024-09-01&tabs=HTTP My issue: I observed unauthorized activity on our Sentinel workspace. The Azure Activity Logs clearly indicate the user involved, the resource, and the operation type: "MICROSOFT.SECURITYINSIGHTS/ENTITIES/ACTION" But that’s it. No detail about what the action was, what entity it targeted, or how it was triggered. This makes auditing extremely difficult. It's clear the person was in Sentinel and perform an activity through it, from search, KQL, logs to find an entity from a KQL query. But, that's all... Strangely, this operation is not even listed in the official Sentinel Operations documentation linked above. My question: Has anyone encountered this and found a way to interpret this operation type properly? Any insight into how to retrieve more meaningful details (action context, target entity, etc.) from these events would be greatly appreciated.
Sentinel Data Connector for Azure Virtual Desktop
Hello, I have a customer planning to deploy Azure Virtual Desktop (AVD). They are currently using Microsoft Sentinel for their SecOps. However, there is no AVD Data Connector available. The customer is not interested in building a custom data connector. Does anyone know if there are plans to add a data connector for AVD in the near future? Thanks.
Daily "Network Port Sweep detected on port x" but no Source IP
For a couple of months we have been getting "Network Port Sweep was detection by multiple IPs" with ports 135 and 445 mostly. The KQL attached lists a load of Destination IPs but no Source IP (see example below) All these are inside our network, and so not coming from outside the network where the firewall would block such scans. We suspect it is one of our network tools such as Solarwinds but without the Source IP it is difficult to prove anything. // The query_now parameter represents the time (in UTC) at which the scheduled analytics rule ran to produce this alert. set query_now = datetime(2024-06-24T03:01:10.2587643Z); let lookback = 1h; let threshold = 20; _Im_NetworkSession(starttime=ago(lookback), endtime=now()) | where NetworkDirection == "Inbound" | summarize make_set(DstIpAddr, 100) by DstPortNumber | where array_length(set_DstIpAddr) > threshold Tried to modify the query, this is the KQL I have tried. set query_now = datetime(2024-01-26T07:47:48.3756000Z); let lookback = 1h; let threshold = 20; _Im_NetworkSession(starttime=ago(lookback), endtime=now()) | where NetworkDirection == "Inbound" | summarize make_set(DstIpAddr, 100), make_set(SrcIpAddr, 100) by DstPortNumber | where array_length(set_DstIpAddr) > threshold Anyone got any suggestions on how we can track down what is causing this alert in Sentinel?
I am learning to build Logic Apps working with Sentinel inc
Hello I am learning to build Logic Apps. The tasks will mainly involve querying Log Analytics and writing comments in incidents. How can I do this securely? I understand that I need to add the Sentinel Contributor role for the Logic App, but what next? If I need the Logic App to be able to query, do I need to give it additional access, such as Log Analytics Contributor or Reader? When I want to create a connection, I have three options: OAuth - I see that I log in with my account, and then the Logic App has access to what I have access to. Is this secure? Service Principal - I need to register an application and create a secret for it, then grant this application access to Sentinel. Can I use a single Service Principal for all Logic Apps? I understand that secrets need to be rotated – does this affect my Logic Apps? Will I need to update something to ensure everything works properly? Managed Identity - This only works within the specific Logic App? This seems like the best solution, but I managed to add a new Managed Identity to query Log Analytics, and in the next step, I wanted it to add tasks to an incident in Sentinel, and unfortunately, it didn't work. (However, I changed the last step and added it via OAuth, and it worked, allowing the Logic App to add tasks to the incident in Sentinel.) this is one of example i am working on. https://github.com/Azure/Azure-Sentinel/blob/master/Playbooks/Get-SOCTasks/readme.md adding role assignment I would be great if you can share your experiences! thank youFinOps In Microsoft Sentinel
Microsoft Sentinel's security analytics and operations data is stored in an Azure Monitor Log Analytics workspace. Billing is based on the volume of data analyzed in Microsoft Sentinel and stored in the Log Analytics workspace. The cost of both is combined in a simplified pricing tier. Microsoft 365 data sources are always free to ingest for all Microsoft Sentinel users: Billable data sources: Although alerts are free, the raw logs for Microsoft Endpoint Defender, Defender for Cloud Apps, Microsoft Entra ID sign in and audit logs, and Azure Information Protection (AIP) data types are paid: Microsoft Sentinel data retention is free for the first 90 days. Enable Microsoft Sentinel on an Azure Monitor Log Analytics workspace and the first 10 GB/day is free for 31 days. The cost for both Log Analytics data ingestion and Microsoft Sentinel analysis charges up to the 10 GB/day limit are waived during the 31-day trial period. This free trial is subject to a 20 workspace limit per Azure tenant • By default, all tables in your workspace inherit the workspace's interactive retention setting and have no archive. • You can modify the retention and archive settings of individual tables Azure Monitor Logs retains data in two states: - Interactive retention: Lets you retain Analytics logs for interactive queries of up to 2 years. - Archive: Lets you keep older, less used data in your workspace at a reduced cost. • You can access data in the archived state by using search jobs, restore and keep data in archived state for up to 12 years • Its very important for cost management in MS Sentinel when you define short data retention period, but firstly go in Log Analytics WS | Workbooks | Workspace Usage in order to see tables size Use this workbook to analyze the the sizes of the different tables in your workspace: Where can save your money? Ingestion • Carefully plan what data is sent into your Microsoft sentinel workspace • Utilize filtering mechanisms to reduce ingestions to what the SOC needs • Set daily cap (good for PoC scenarios but not recommend for production) Retention • Send data to other storage platforms that have cheaper storage costs (Azure blob storage, Azure data explorer) Compute • Shutdown Azure machine learning compute during off hours, consider using reserved instances pricing • Set quotas on your subscription and workspaces • Use low-priority virtual machine (VM) Bandwidth • Sending data across Azure regions might incur into additional costs Ingestion planning • Analyze your data sources and decides what data is needed by your SOC for detection, investigations, hunting and enrichment. Take use-driven approach • Plan your workspace design • Existing workspaces might be ingesting data not needed by the SOC • Consider using separate workspace for Microsoft Sentinel • When possible enable Defender for Servers on the same workspace where you enable Microsoft Sentinel, you get 500 MB of free data ingestion per day • If you configure your Log Analytics agent to send data to two or more different Log Analytics workspaces (multi-homing), you'll get 500-MB free data ingestion for each workspace. Retention • Microsoft Sentinel retention is charged ($0.1/GB/month) and can become a big portion of the Microsoft Sentinel cost • 1.2 TB/day ingestion with 1-year retention (East US list prices) Ingestion: ~ $89К/month Retention: ~ $33К/month • If you require more than 90 days retention, determine if you need it for the whole workspace or just some tables • Consider using other storage platform for long storage retention (Azure blob storage, Azure data explorer) Long term retention options: • Azure blob storage • Cheaper than Microsoft sentinel retention • Difficult for query • Ideal for audit/compliance purposes Azure Data explorer Stores security logs in Azure Data Explorer on a long-term basis. Minimizes costs and provides easy access when you need to query the data and stores most of the data in the cold cache, minimizing the computing cost. Log Analytics doesn't currently support exporting custom log tables. In this scenario, you can use Azure Logic Apps to export data from Log Analytics workspaces. Because Azure Data Explorer provides long-term storage, you can reduce your Sentinel retention costs with this approach and ideal for forensic investigation and hunting on older data Can achieve up to 75% saving on retention costs Instead of using Azure Data Explorer for long-term storage of security logs, you can use Storage. This approach simplifies the architecture and can help control the cost. A disadvantage is the need to rehydrate the logs for security audits and interactive investigative queries. With Azure Data Explorer, you can move data from the cold partition to the hot partition by changing a policy. This functionality speeds up data exploration. Bandwidth Sending telemetry from one Azure region to another can incur in bandwidth costs this only affect Azure VMs that send telemetry across Azure regions data sources based on diagnostics settings are not affected not a big cost component compared to ingestion or retention Example: 1000 VMs, where each generates 1GB/day, sending data from US to EU: 1000 VMs * 1GB/day *30 days/month*$0.05/GB =$1.500/month Ingestion Cost Alert Playbook Managing cost for cloud services is an essential part of ensuring that you get maximum value for your investment in solutions running on this computing platform. Azure Sentinel is no different. To help you exercise greater control over your budget for Azure Sentinel this playbook will send you an alert should you exceed a budget that you define for your Azure Sentinel Workspace within a given time-frame With the ingestion cost alert playbook, you can set up an alert based on the budget defined in your Microsoft Sentinel workspace within a given timeframe. Ingestion Anomaly Alert Playbook This playbook sends you an alert should there be an ingestion spike into your workspace. The playbook uses the series_decompose_anomalies KQL function to determine anomalous ingestion The Workspace Usage Report workbook The Workspace Usage Report workbook provides your workspace's data consumption, cost, and usage statistics. The workbook gives the workspace's data ingestion status and amount of free and billable data. You can use the workbook logic to monitor data ingestion and costs, and to build custom views and rule-based alerts. This workbook also provides granular ingestion details. The workbook breaks down the data in your workspace by data table, and provides volumes per table and entry to help you better understand your ingestion patterns. Azure pricing model – based on volume of data ingested User Entity Behavior Analytics Approximately 10% of the cost of logs selected for UEBA Reduce To change your pricing tier commitment, select one of the other tiers on the pricing page, and then select Apply. You must have Contributor or Owner role in Microsoft Sentinel to change the pricing tier costs for Microsoft Sentinel Useful links: Tools that are related to FinOps on Azure Sentinel (Azure Pricing Calculator, Azure Cost Management, Azure Advisor, TCO Calculator, Azure Hybrid Benefit Savings Calculator) https://techcommunity.microsoft.com/t5/fasttrack-for-azure/the-azure-finops-guide/ba-p/3704132 Manage and monitoring Costs for Microsoft Sentinel https://learn.microsoft.com/en-us/azure/sentinel/billing-monitor-costs Reduce costs for Microsoft Sentinel https://learn.microsoft.com/en-us/azure/sentinel/billing-reduce-costs Ingestion Cost Spike Detection Playbook https://techcommunity.microsoft.com/t5/microsoft-sentinel-blog/ingestion-cost-spike-detection-playbook/ba-p/2591301 Ingestion Cost Alert Playbook https://techcommunity.microsoft.com/t5/microsoft-sentinel-blog/ingestion-cost-alert-playbook/ba-p/2006003 Introducing Microsoft Sentinel Optimization Workbook https://techcommunity.microsoft.com/t5/microsoft-sentinel-blog/introducing-microsoft-sentinel-optimization-workbook/ba-p/3901489
Query All Logs/sources for Credit Card Numbers
We thought this might be something that Microsoft Sentinel could have some built in functionality for but seems we cannot find it. We are looking to be able to query all of our log sources for any credit card numbers but I cannot seem to think of a great way to do this and I don't believe union is possible in an analytics rule. Has anyone else created logic in KQL to potentially solve this gap in the solution? Happy to post our regex here as well: (.*)((?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|3[47][0-9]{13}|6(?:011|5[0-9]{2})[0-9]{12}))(.*) Common Goal: 1. Query the log source(s) for the specific regex 2. Parse the field identified as matching the regex so we can capture where it matches and go from there, not just that a "match exists" This seems rather easy but also....struggling to think of a good way to make this happen especially across all log sources rather than querying one table at a time.Add Service Principal
I have noticed an "Add service principal" operation in the Azure audit log. I asked my team about it, but they also don't know about this operation. In normal operations, we can find the actor in the "Initiated by" field. However, in this event, there is no "Initiated by" actor specified. Instead, the "Identity" field displays "Microsoft Azure AD Internal - Jit Provisioning." Is this automatically added by Azure?
