CVE-2021-31979: Microsoft Windows Kernel Privilege Escalation Vulnerability

Vulnerability summary

CVE-2021-31979 is a high (CVSS 7.8) vulnerability in Microsoft Windows. It is known to be exploited: CISA lists it, first on 03-11-2021. EPSS estimates a 4.54% chance of exploitation in the next 30 days, higher than 91.4% of scored vulnerabilities.

Timeline

1. 14-07-2021
   PublishedVulnerability first disclosed.
2. 03-11-2021
   Added to CISA KEVMicrosoft Windows Kernel Privilege Escalation Vulnerability
3. 17-11-2021
   CISA remediation dueApply updates per vendor instructions.
4. 07-10-2026
   Last modifiedVulnerability information updated.

Description

Windows Kernel Elevation of Privilege Vulnerability

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.