CVE-2026-81963

high

Description

Improper link resolution before file access ('link following') in Windows Update Stack allows an authorized attacker to elevate privileges locally.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963

https://www.malwarebytes.com/blog/news/2026/09/microsoft-fixes-record-964-flaws-including-2-exploited-zero-days

https://www.helpnetsecurity.com/2026/09/09/september-2026-patch-tuesday-zero-days-sigred-successor/

https://thehackernews.com/2026/09/microsoft-patches-record-974-flaws.html

https://securityaffairs.com/198705/security/microsofts-biggest-patch-tuesday-974-cves-2-zero-days-and-20-wormable-bugs.html

https://www.securityweek.com/microsoft-patches-record-974-vulnerabilities-including-two-exploited-zero-days/

https://cyberscoop.com/microsoft-patch-tuesday-september-2026/

https://www.tenable.com/blog/microsofts-september-2026-patch-tuesday-addresses-964-cves-cve-2026-81963-cve-2026-85880

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963

Details

Source: Mitre, NVD

Published: 2026-09-08

Updated: 2026-09-09

Known Exploited Vulnerability (KEV)

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

Severity: Medium

CVSS v3

Base Score: 7.8

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00631