Forum Discussion
Windows Update and security fixes.
I think because that article says:
"Applies to: Windows 10, version 1903, Windows 10, version 1809, Windows 10, version 1803, Windows 10, version 1709, Windows 10, version 1607, Windows 10, Windows RT 8.1, Windows 8.1, Windows 7 Service Pack 1"
and there is no mention of 1909 in that entire page, so it's safe to assume that it is already fixed in version 1909, otherwise Microsoft would have included it in the article as well.
HotCakeXI totally agree with your analyze. The issue is that in reality, according to Microsoft expert internal tests, it is not yet safe or fixed with 1909 version. You still need to manually modify registry.
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Xavier_2020 wrote:HotCakeXI totally agree with your analyze. The issue is that in reality, according to Microsoft expert internal tests, it is not yet safe or fixed with 1909 version. You still need to manually modify registry.
Could you please show me that internal test results?
Microsoft do not gave me there internal test, so I can't, but I am confidant of the information that they gave me and action they ask me to do.
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Xavier_2020 wrote:Microsoft do not gave me there internal test, so I can't, but I am confidant of the information that they gave me and action they ask me to do.
I mean you can believe whatever you like but for me proof is important,
I think dretzer wrote a complete answer:
I think you misunderstood the side-channel mitigations article.
If you have all Updates installed on a current Windows 10 (1809, 1903, 1909), and your firmware has the correct cpu microcode, you don't have to edit the registry.
The article you linked to describes methods to disable certain mitigations if you run into problems, or enable special cases.
If we talk about Windows Server, then it is a different story. There you have to manually activate part of the mitigations. As many of these mitigations can cost a substantial ammount of performance in certain server environments, it would not be wise to enable them without an admin testing it first.
To sum it up:
For Windows 10 Clients with Intel CPU, ALL operatingsystem-mitigations, except system-wide speculative store bypass mitigation, are enabled by default. You do NOT need to touch the registry if you don't have a special case where SSBD is a problem. SSBD-mitigations are only needed if you run vulnerable software. All operating system binaries are not vulnerable to SSBD. Be aware that system-wide SSBD-mitigation will impact end-user performance!
For Windows Server 2019 with Intel CPU, you have to set 2 registry keys (FeatureSettingsOverride = 0, FeatureSettingsOverrideMask = 3) to get the same protections as a Windows 10 Client. You can easily set these keys for your servers with group policy.
You need firmware-updates for your hardware to mitigate some of the vulnerabilites! you cannot mitigate side-channel vulnerabilites with windows updates and/or registry keys alone!
If you want to know the protection state of a system, open powershell and install the speculationcontrol module. With this module you can use "get-speculationcontrolsettings" to get a complete rundown of side-channel-protections and vulnerabilites. It will tell you if your hardware is vulnerable in the first place, if os-mitigations are enabled and if hardware-support for this mitigations is available.
If it tells you to update your device firmware, you need to check with your oem, or you will be vulnerable anyway.
dretzer a écrit :If you have all Updates installed on a current Windows 10 (1809, 1903, 1909), and your firmware has the correct cpu microcode, you don't have to edit the registry.
If you want to know the protection state of a system, open powershell and install the speculationcontrol module. With this module you can use "get-speculationcontrolsettings" to get a complete rundown of side-channel-protections and vulnerabilites. It will tell you if your hardware is vulnerable in the first place, if os-mitigations are enabled and if hardware-support for this mitigations is available.
If it tells you to update your device firmware, you need to check with your oem, or you will be vulnerable anyway.
The first point is not my experience.
In a PC with updated CPU microcode, AND Windows with all latest updates done by Windows Update is not enough to mitigate all CPU vulnerabilities according “PowerShell SpeculationControl script”.
I still need to edit registry, and “PowerShell SpeculationControl script” confirm that (before and after test output to control that). Mitigations was already done before 1909 build updates.
Just to help users and administrators here, the link of the “PowerShell SpeculationControl script”.
https://www.powershellgallery.com/packages/SpeculationControl/
https://support.microsoft.com/en-us/help/4074629/understanding-the-output-of-get-speculationcontrolsettings-powershell
To give you some real-world examples, I checked three different machines with freshly installed Windows 10 1909 and Windows Server 2019. One machine uses a 7th gen Core i7, the other one a 10th gen and the server uses a Xeon D. As you see, only the Windows Server instance would need a registry setting to enable BTIWindowsSupport. The Windows 10 Clients have all needed mitigations enabled without touching the registry. System-Wide SSBD being the only exception, which, as I explained, should not be necessary on a normal system.
Windows 10 1909 on Intel(R) Core(TM) i7-7500U
BTIHardwarePresent : True
BTIWindowsSupportEnabled : True
BTIDisabledBySystemPolicy : False
BTIDisabledByNoHardwareSupport : False
BTIKernelRetpolineEnabled : False
BTIKernelImportOptimizationEnabled : True
KVAShadowRequired : True
KVAShadowWindowsSupportPresent : True
SSBDWindowsSupportPresent : True
SSBDHardwareVulnerable : True
SSBDHardwarePresent : True
SSBDWindowsSupportEnabledSystemWide : False
L1TFHardwareVulnerable : True
L1TFWindowsSupportEnabled : True
L1TFInvalidPteBit : 45
L1DFlushSupported : True
MDSWindowsSupportPresent : True
MDSHardwareVulnerable : True
MDSWindowsSupportEnabled : TrueWindows 10 1909 on Intel(R) Core(TM) i7-1065G7
BTIHardwarePresent : True
BTIWindowsSupportPresent : True
BTIWindowsSupportEnabled : True
BTIDisabledBySystemPolicy : False
BTIDisabledByNoHardwareSupport : False
BTIKernelRetpolineEnabled : False
BTIKernelImportOptimizationEnabled : True
KVAShadowRequired : False
KVAShadowWindowsSupportPresent : True
KVAShadowWindowsSupportEnabled : False
KVAShadowPcidEnabled : False
SSBDWindowsSupportPresent : True
SSBDHardwareVulnerable : True
SSBDHardwarePresent : True
SSBDWindowsSupportEnabledSystemWide : False
L1TFHardwareVulnerable : False
L1TFWindowsSupportPresent : True
L1TFWindowsSupportEnabled : False
L1TFInvalidPteBit : 0
L1DFlushSupported : True
MDSWindowsSupportPresent : True
MDSHardwareVulnerable : False
MDSWindowsSupportEnabled : FalseWindows Server 2019 on Intel(R) Xeon(R) D-2183IT
BTIWindowsSupportPresent : True
BTIWindowsSupportEnabled : False
BTIDisabledBySystemPolicy : True
BTIDisabledByNoHardwareSupport : False
BTIKernelRetpolineEnabled : False
BTIKernelImportOptimizationEnabled : True
KVAShadowWindowsSupportEnabled : True
KVAShadowPcidEnabled : True
SSBDWindowsSupportPresent : True
SSBDHardwareVulnerable : True
SSBDHardwarePresent : True
SSBDWindowsSupportEnabledSystemWide : False
L1TFWindowsSupportPresent : True
L1TFWindowsSupportEnabled : True
L1TFInvalidPteBit : 45
L1DFlushSupported : True
MDSWindowsSupportPresent : True
MDSHardwareVulnerable : True
MDSWindowsSupportEnabled : TrueIf you don't understand the output of get-speculationcontrolsettings, just ask for specifics and I'll try to explain.
