CVE-2021-36942
CVE-2021-36942 is a high-severity vulnerability in Microsoft Windows Server 2004 with a CVSS 3.x base score of 7.5. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03).
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 66% (99th percentile)
- Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
- EU (EUVD) id: EUVD-2021-23518
- EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
- Affected product: Microsoft Windows Server 2004
- Published:
- Last modified:
Description
Windows LSA Spoofing Vulnerability
Frequently asked questions
- What is CVE-2021-36942?
- Windows LSA Spoofing Vulnerability
- How severe is CVE-2021-36942?
- CVE-2021-36942 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2021-36942 being actively exploited?
- Yes. CVE-2021-36942 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
- What products are affected by CVE-2021-36942?
- CVE-2021-36942 primarily affects Microsoft Windows Server 2004. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-36942?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
- Does CVE-2021-36942 have an EU (EUVD) identifier?
- Yes. CVE-2021-36942 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-23518. It is also flagged as exploited in the EUVD (since 2021-11-03).
- When was CVE-2021-36942 published?
- CVE-2021-36942 was published on 2021-08-12 and last updated on 2026-08-10.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36942
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-36942
- https://www.kb.cert.org/vuls/id/405600
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36942
Affected products (8)
- cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
- cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*
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