CVEs / CVE-2026-85880
CVE-2026-85880: Microsoft Windows Heap-Based Buffer Overflow Vulnerability
- Known exploited in the CISA KEV catalog since 8 Sep 2026
- high 7.8 CVSS 3.1 (from the CNA)
- EPSS 0.38% chance of exploitation in the next 30 days, higher than 32% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Microsoft Windows Advanced Local Procedure Call contains a heap-based buffer overflow vulnerability that allows an attacker to elevate privileges locally.
Description
Heap-based buffer overflow in Windows ALPC allows an authorized attacker to elevate privileges locally.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows 10 Version 1607 | from 10.0.14393.0, before 10.0.14393.9512 | 10.0.14393.9512 |
| Microsoft Windows 10 Version 1809 | from 10.0.17763.0, before 10.0.17763.9245 | 10.0.17763.9245 |
| Microsoft Windows 10 Version 21H2 | from 10.0.19044.0, before 10.0.19044.7725 | 10.0.19044.7725 |
| Microsoft Windows 10 Version 22H2 | from 10.0.19045.0, before 10.0.19045.7725 | 10.0.19045.7725 |
| Microsoft Windows Server 2012 | from 6.2.9200.0, before 6.2.9200.26349 | 6.2.9200.26349 |
| Microsoft Windows Server 2012 (Server Core installation) | from 6.2.9200.0, before 6.2.9200.26349 | 6.2.9200.26349 |
| Microsoft Windows Server 2012 R2 | from 6.3.9600.0, before 6.3.9600.23398 | 6.3.9600.23398 |
| Microsoft Windows Server 2012 R2 (Server Core installation) | from 6.3.9600.0, before 6.3.9600.23398 | 6.3.9600.23398 |
| Microsoft Windows Server 2016 | from 10.0.14393.0, before 10.0.14393.9512 | 10.0.14393.9512 |
| Microsoft Windows Server 2016 (Server Core installation) | from 10.0.14393.0, before 10.0.14393.9512 | 10.0.14393.9512 |
| Microsoft Windows Server 2019 | from 10.0.17763.0, before 10.0.17763.9245 | 10.0.17763.9245 |
| Microsoft Windows Server 2019 (Server Core installation) | from 10.0.17763.0, before 10.0.17763.9245 | 10.0.17763.9245 |
| Microsoft Windows Server 2022 | from 10.0.20348.0, before 10.0.20348.5622 | 10.0.20348.5622 |
Exploitation
| In CISA KEV since | 8 Sep 2026 |
|---|---|
| Due date for US federal agencies | 22 Sep 2026 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 7.8 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-122, CWE-908 |
References
- CVE-2026-85880 on NVD
- CVE-2026-85880 in the CISA KEV catalog
- https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-85880 (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (cited by CISA)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85880 Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-85880 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.