CVEs / CVE-2021-36942
CVE-2021-36942: Microsoft Windows Local Security Authority (LSA) Spoofing Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- medium 5 CVSS 2.0 (NVD)
- EPSS 66% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Microsoft Windows Local Security Authority (LSA) contains a spoofing vulnerability allowing an unauthenticated attacker to call a method on the LSARPC interface and coerce the domain controller to authenticate against another server using NTLM.
Description
Windows LSA Spoofing Vulnerability
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows Server 2008 R2 Service Pack 1 | from 6.1.7601.0, before 6.1.7601.25685 | 6.1.7601.25685 |
| Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation) | from 6.1.7601.0, before 6.1.7601.25685 | 6.1.7601.25685 |
| Microsoft Windows Server 2008 Service Pack 2 | from 6.0.6003.0, before 6.0.6003.21192 | 6.0.6003.21192 |
| Microsoft Windows Server 2008 Service Pack 2 (Server Core installation) | from 6.0.6003.0, before 6.0.6003.21192 | 6.0.6003.21192 |
| Microsoft Windows Server 2012 | from 6.2.9200.0, before 6.2.9200.23435 | 6.2.9200.23435 |
| Microsoft Windows Server 2012 (Server Core installation) | from 6.2.9200.0, before 6.2.9200.23435 | 6.2.9200.23435 |
| Microsoft Windows Server 2012 R2 | from 6.3.9600.0, before 6.3.9600.20094 | 6.3.9600.20094 |
| Microsoft Windows Server 2012 R2 (Server Core installation) | from 6.3.9600.0, before 6.3.9600.20094 | 6.3.9600.20094 |
| Microsoft Windows Server 2016 | from 10.0.14393.0, before 10.0.14393.4583 | 10.0.14393.4583 |
| Microsoft Windows Server 2016 (Server Core installation) | from 10.0.14393.0, before 10.0.14393.4583 | 10.0.14393.4583 |
| Microsoft Windows Server 2019 | from 10.0.17763.0, before 10.0.17763.2114 | 10.0.17763.2114 |
| Microsoft Windows Server 2019 (Server Core installation) | from 10.0.17763.0, before 10.0.17763.2114 | 10.0.17763.2114 |
| Microsoft Windows Server version 2004 | from 10.0.0, before 10.0.19041.1165 | 10.0.19041.1165 |
| Microsoft Windows Server version 20H2 | from 10.0.0, before 10.0.19042.1165 | 10.0.19042.1165 |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 17 Nov 2021 |
| Used in ransomware campaigns | Known |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 2.0 | 5 mediumAV:N/AC:L/Au:N/C:N/I:P/A:NScored by NVD |
|---|
References
- CVE-2021-36942 on NVD
- CVE-2021-36942 in the CISA KEV catalog
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36942 Patch, Vendor Advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36942 Patch, Vendor Advisory
- https://www.kb.cert.org/vuls/id/405600 Exploit, Third Party Advisory, US Government Resource
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36942 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.