CVE-2026-81963KEV · OVERDUECWE-284CWE-59broken-access-control

Microsoft Windows Link Following Vulnerability

High · published September 8, 2026

Patch now

Confirmed exploited, and the score agrees

CVSS calls it high at 7.8. It is confirmed in active exploitation. It sits in the 32.3th percentile for exploit probability.

31
days past CISA
deadline
CVSS v3.1
7.8
EPSS
0%
Percentile
32.3
In the wild
Confirmed
What it is

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

The record
Technical detail
CVSS v3.1
7.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00393 · 32.3th percentile
Weaknesses
CWE-284 · Improper Access Control; CWE-59 · Improper Link Resolution Before File Access ('Link Following')
Published
2026-09-08T22:21Z
KEV added
2026-09-08 · due 2026-09-22
Affected products (9)
ProductVersionsFixed in
microsoft/windows_11_23h2< 10.0.22631.758210.0.22631.7582
microsoft/windows_11_23h2< 10.0.22631.758210.0.22631.7582
microsoft/windows_11_24h2< 10.0.26100.944510.0.26100.9445
microsoft/windows_11_24h2< 10.0.26100.944510.0.26100.9445
microsoft/windows_11_25h2< 10.0.26200.944510.0.26200.9445
microsoft/windows_11_25h2< 10.0.26200.944510.0.26200.9445
microsoft/windows_11_26h1< 10.0.28000.295410.0.28000.2954
microsoft/windows_11_26h1< 10.0.28000.295410.0.28000.2954
microsoft/windows_server_2025< 10.0.26100.3343810.0.26100.33438
References (2)
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-81963 · [email protected]https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81963 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 10 SEP 03:18Z
    EPSS moved — → 1%
    epss
  • 08 SEP 17:19Z
    Windows Update Stack Elevation of Privilege Vulnerability
    cvelistv5