SB2026090867 - Privilege escalation in Microsoft Windows ALPC
Published: September 8, 2026
Security Bulletin ID
SB2026090867
CSH Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Heap-based buffer overflow (CVE-ID: CVE-2026-85880) Exploited
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 9.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H]
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error in Windows ALPC. A local user can trigger a heap-based buffer overflow and execute arbitrary code with SYSTEM privileges.
Note, the vulnerability is being actively exploited in the wild.
Remediation
Install update from vendor's website.