CVE-2021-36942
HighExploitedPublic exploitWindows LSA Spoofing Vulnerability
Published May 11, 2022 · Updated Aug 10, 2026 · Also known as TR-22-0343
Key Facts
Patch immediately- CVE-2021-36942 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Windows Server 2004 (Microsoft), windows server 2008 R2 (Microsoft), Windows Server 2008 (Microsoft) and 6 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Aug 24, 2021 and is known to be used in ransomware campaigns. Public exploit code is available.
- EPSS estimates a 66% probability of exploitation in the next 30 days.
- Fixed versions are available, including Windows Server 2004 10.0.19041.1165, windows server 2008 R2 6.1.7601.25685, Windows Server 2008 Sp2 6.0.6003.21192.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS (30-day exploit likelihood)
66%
Higher than 99.2% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings, used by ransomware
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-36942 brief as a PDF
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Description
Windows LSA Spoofing Vulnerability
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | Nov 17, 2021 | Known |
| Industry KEV feed | Aug 24, 2021 | Nov 17, 2021 | Known |
| CIRCL KEV | Nov 3, 2021 | Nov 17, 2021 | Known |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
17 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Windows Server 2004Microsoft | 10.0.19041.1165 | 10.0.19041.1165 |
| windows server 2008 R2Microsoft | 6.1.7601.25685 | 6.1.7601.25685 |
| Windows Server 2008Microsoft | r2-sp1 | n/a |
| Windows Server 2008 Sp2Microsoft | 6.0.6003.21192 | 6.0.6003.21192 |
| Windows Server 2012Microsoft | 6.2.9200.23435, r2 | 6.2.9200.23435 |
Patched Releases
Windows Server 2004
10.0.19041.1165
windows server 2008 R2
6.1.7601.25685
Windows Server 2008 Sp2
6.0.6003.21192
Windows Server 2012
6.2.9200.23435
windows server 2012 R2
6.3.9600.20094
Windows Server 2016
10.0.14393.4583
Windows Server 2019
10.0.17763.2114
windows server 20H2
10.0.19042.1165
Timeline
Added to Industry KEV feed
Aug 24, 2021
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Publicly disclosed
May 11, 2022
Last updated
Aug 10, 2026
References
- advisoryhttps://docs.microsoft.com/en-us/deployedge/microsoft-edge-relnotes-security
- advisoryhttps://docs.microsoft.com/en-us/windows/win32/secauthn/lsa-authentication
- advisoryhttps://en.wikipedia.org/wiki/NT_LAN_Manager
- advisoryhttps://msrc.microsoft.com/update-guide/releaseNote/2022-May
- advisoryhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2022-22012
FAQ
Common Questions.
Windows LSA Spoofing Vulnerability
Affected: Windows Server 2004 (Microsoft) versions 10.0.19041.1165; windows server 2008 R2 (Microsoft) versions 6.1.7601.25685; Windows Server 2008 (Microsoft) versions r2-sp1, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Aug 24, 2021 and is known to be used in ransomware campaigns.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of Nov 17, 2021.
Public exploit code is available.
Fixed versions are available, including Windows Server 2004 10.0.19041.1165, windows server 2008 R2 6.1.7601.25685, Windows Server 2008 Sp2 6.0.6003.21192.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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