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CVE-2022-21971 Microsoft CVE debrief

CVE-2022-21971 is a Microsoft Windows Runtime remote code execution vulnerability that CISA added to its Known Exploited Vulnerabilities catalog on 2022-08-18. Because it is a KEV-listed issue, defenders should treat it as a high-priority patching item even though the public record provided here does not include deeper technical detail or a CVSS score. The practical takeaway is straightforward: follow Microsoft’s update guidance, confirm the fix is deployed, and make sure affected Windows systems are not left exposed past CISA’s due date of 2022-09-08.

Vendor
Microsoft
Product
Windows
CVSS
Unknown
CISA KEV
Listed
Original CVE published
2022-08-18
Original CVE updated
2022-08-18
Advisory published
2022-08-18
Advisory updated
2022-08-18

Who should care

Windows administrators, endpoint security teams, vulnerability management teams, and asset owners responsible for Microsoft Windows fleets should prioritize this CVE. Security teams managing compliance against CISA KEV should also track it closely.

Technical summary

CVE-2022-21971 is described as a Microsoft Windows Runtime remote code execution vulnerability. The supplied public record does not include exploit mechanics, affected versions, or a CVSS score. What is clearly documented is that CISA marked it as known exploited and directed organizations to apply vendor updates.

Defensive priority

High. CISA KEV inclusion indicates known exploitation and a required remediation deadline, so this vulnerability should be prioritized over non-KEV findings with similar or lower operational impact.

Recommended defensive actions

  • Apply Microsoft’s security updates according to vendor instructions as soon as possible.
  • Verify that the remediation is fully deployed across the Windows estate, including managed and remote endpoints.
  • Prioritize systems with broad user access or elevated business criticality for validation and rollout checks.
  • Use the CISA KEV due date of 2022-09-08 as the remediation target for compliance tracking.
  • Monitor Microsoft MSRC and NVD references for any additional guidance or clarifications.

Evidence notes

The debrief is based on the supplied CISA Known Exploited Vulnerabilities record and the associated official reference links. The source item lists CVE-2022-21971 as a Microsoft Windows Runtime remote code execution vulnerability, with dateAdded 2022-08-18, dueDate 2022-09-08, and requiredAction 'Apply updates per vendor instructions.' The supplied record also points to the Microsoft MSRC update guide and NVD detail page as supporting references. No exploit code, affected-version breakdown, or unsupported technical claims are included here.

Official resources

Publicly documented by CISA in the Known Exploited Vulnerabilities catalog on 2022-08-18. This brief intentionally omits exploit details and includes only defensive, source-backed information.