Windows Security Account Manager: Security feature bypass via race condition
Summary
Microsoft fixed a time-of-check time-of-use (TOCTOU) race condition in the Windows Security Account Manager Remote Protocol. An attacker on the network without privileges or user interaction could bypass a security feature by winning a race against the system's check. Attack complexity is high and the impact is limited to integrity, with no confidentiality or availability impact documented.
Affected
- Windows 10 Version 1607, 1809, 21H2, 22H2
- Windows 11 Version 23H2, 24H2, 25H2, 26H1, 26H2
- Windows Server 2016 (including Server Core), 2019 (including Server Core), 2022
Build ranges as listed in the CVE record.
Fixed in
- Windows 10 1607: 10.0.14393.9688
- Windows 10 1809: 10.0.17763.9487
- Windows 10 21H2: 10.0.19044.7846
- Windows 10 22H2: 10.0.19045.7846
- Windows 11 23H2: 10.0.22631.7711
- Windows 11 24H2: 10.0.26100.9974 (unconfirmed by a secondary source)
- Windows 11 25H2: 10.0.26200.9974
- Windows 11 26H1: 10.0.28000.3501
- Windows 11 26H2: 10.0.26300.9974
- Windows Server 2016: 10.0.14393.9688
- Windows Server 2019: 10.0.17763.9487
- Windows Server 2022: 10.0.20348.5870
Based on the CVE record; verify on the MSRC advisory.
Workaround
Unknown.
Exploitation
- No known exploitation in the wild.
- Microsoft assesses exploitation as less likely; the flaw is not publicly disclosed.
- CISA SSVC: exploitation none, not automatable.
- No public proof of concept found.
Our recommendation
- Install the November 2026 security update, or the fixed build for your version, on all affected systems. Prioritise domain controllers and internet-facing Windows hosts.
- Windows 10 1607 and 1809 are out of mainstream support; enrol in Extended Security Updates where required.
- Restrict access to SAM remote interfaces to internal networks and block them at the perimeter.
- Verify the fixed builds on the MSRC advisory before deployment.
- Check NVD once analysis is complete.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Security feature bypass – Windows Security Account Manager
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5131291, KB5131085, KB5131096, KB5131090, KB5131087, KB5132061
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-122474 msrc.microsoft.com
- CVE Record CVE-2026-122474 www.cve.org
- Rapid7: Patch Tuesday November 2026 www.rapid7.com
- BleepingComputer: November 2026 Patch Tuesday www.bleepingcomputer.com
- Strix: CVE-2026-122474 www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 15:12.
Original description (NVD)
Time-of-check time-of-use (toctou) race condition in Windows Security Account Manager allows an unauthorized attacker to bypass a security feature over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
Affected? We can help.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.