Independent & educational platform Not a government body. No link or affiliation with any government organisation. Made for learning only. Test only systems you own or are authorised to test. Become a Partner or Sponsor → Full disclaimer

CVE-2026-85880

high CISA KEV

Microsoft Windows Heap-Based Buffer Overflow Vulnerability

Vendor / product: Microsoft — Windows

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

CVSS
7.8
7.8 (CVSS v3.1)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity source: NVD CVSS v3.1 (secure@microsoft.com)
Timeline (UTC)
Published: 2026-09-08 18:21
Modified: 2026-09-24 23:19
NVD status: Analyzed
Last synced 2 days ago
Verified against the source API 2026-10-27 07:07 UTC
Exploitation
Listed in CISA KEV
Added 2026-09-08 · due 2026-09-22
Known ransomware use: Unknown

Required action (CISA)

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.

Affected products

microsoft / windows_10_1607 <10.0.14393.9512
microsoft / windows_10_1809 <10.0.17763.9245
microsoft / windows_10_21h2 <10.0.19044.7725
microsoft / windows_10_22h2 <10.0.19045.7725
microsoft / windows_server_2012 all versions, r2
microsoft / windows_server_2016 <10.0.14393.9512
microsoft / windows_server_2019 <10.0.17763.9245
microsoft / windows_server_2022 <10.0.20348.5622

Weakness classification (CWE)

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85880
Patch / mitigation: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85880

References

Data sources

CISA KEV — fetched 2026-10-27 06:50 UTC · record ↗
NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗

Learn the basics

Understanding CVEs and CVSS Scores

Related CVEs