Cleartext

Exploited vulnerability CISA KEV

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

Mirrored from CISA KEV 2026.09.23catalog released

In brief

CVE-2026-85880 is a vulnerability in Microsoft Windows that CISA added to its Known Exploited Vulnerabilities catalog on September 8, 2026, meaning there is evidence it is being exploited. US federal civilian agencies must complete the required action by September 22, 2026.

CVE-2026-85880 is a vulnerability in Microsoft Windows that CISA added to its Known Exploited Vulnerabilities catalog on September 8, 2026, meaning there is evidence it is being exploited. US federal civilian agencies must complete the required action by September 22, 2026.
CVE ID
CVE-2026-85880
Vendor / project
Microsoft
Product
Windows
Added to KEV
Due date
Days to remediate
14
Known ransomware use
Unknown
Weakness
CWE-122, CWE-908

CISA 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.

Notes and references #

https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-85880 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-85880

This page reproduces CISA’s catalog entry and is not indexed by search engines until an editor adds analysis. [Editorial analysis pending]

Next steps #