What’s Vulnerable › Vulnerabilities

CVE-2026-85880: Microsoft Windows Heap-Based Buffer Overflow Vulnerability

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: yes — in CISA KEV since 2026-09-08
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-08 · updated 2026-09-24
• Weakness: CWE-122

Description

Heap-based buffer overflow in Windows ALPC allows an authorized attacker to elevate privileges locally.

Affected products

• Microsoft Windows 10 1607: before 10.0.14393.9512 — fixed in 10.0.14393.9512
• Microsoft Windows 10: before 10.0.17763.9245 — fixed in 10.0.17763.9245
• Microsoft Windows 10: before 10.0.19044.7725 — fixed in 10.0.19044.7725
• Microsoft Windows 10: before 10.0.19045.7725 — fixed in 10.0.19045.7725
• Microsoft Windows Server 2012: r2
• Microsoft Windows Server 2016: before 10.0.14393.9512 — fixed in 10.0.14393.9512
• Microsoft Windows Server 2019: before 10.0.17763.9245 — fixed in 10.0.17763.9245
• Microsoft Windows Server 2022: before 10.0.20348.5622 — fixed in 10.0.20348.5622

How to fix

Upgrade to a fixed version: Microsoft Windows 10 1607 10.0.14393.9512; Microsoft Windows 10 10.0.17763.9245; Microsoft Windows 10 10.0.19044.7725; Microsoft Windows 10 10.0.19045.7725; Microsoft Windows Server 2016 10.0.14393.9512; Microsoft Windows Server 2019 10.0.17763.9245; Microsoft Windows Server 2022 10.0.20348.5622. Check the vendor advisory for mitigations.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85880
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-85880

Get alerted when CVE-2026-85880 or the next vulnerability affects your stack