September 8, 2026 · Applied Cybernetics Group
CVE-2026-85880 — Microsoft Windows
Microsoft Windows Heap-Based Buffer Overflow Vulnerability
- Added to KEV
2026-09-08- Federal due date
2026-09-22- Vendor
- Microsoft
- Product
- Windows
- EPSS
- 45.8th percentile (score 0.006, as of
2026-09-16) - NVD CVSS v3.1
- 7.8 (HIGH)
- Ransomware use
- Unknown
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2026-85880
CISA short description
Microsoft Windows Advanced Local Procedure Call contains a heap-based buffer overflow vulnerability that allows an attacker to elevate privileges locally.
Required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
NVD description
Heap-based buffer overflow in Windows ALPC allows an authorized attacker to elevate privileges locally.