CVE-2026-21249
Windows NTLM Spoofing Vulnerability
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Windows NTLM Spoofing Vulnerability
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
- Record
CVE-2026-21249- CVSS 3.1
- 3.3 Low
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C - Weakness
- CWE-73
- Updated
- 2026-11-02
EUVDEUVD-2026-7323
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
- Record
EUVD-2026-7323- CVSS 3.1
- 3.3 Low
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-w882-rf7q-923g
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform...
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
- Record
GHSA-w882-rf7q-923g- CVSS 3.1
- 3.3 Low
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-73
- Updated
- 2026-11-02
NVD
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
- Record
CVE-2026-21249- CVSS 3.1
- 3.3 Low
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-73
- Updated
- 2026-11-02
Affected products
- microsoft windows 10 version 1607
- microsoft windows 10 version 1809
- microsoft windows 10 version 21h2
- microsoft windows 10 version 22h2
- microsoft windows 11 version 22h3
- microsoft windows 11 version 23h2
- microsoft windows 11 version 24h2
- microsoft windows 11 version 25h2
- microsoft windows 11 version 26h1
- microsoft windows server 2012 r2
- microsoft windows server 2012 r2 (server core installation)
- microsoft windows server 2016
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- microsoft windows server 2016 (server core installation)
- microsoft windows server 2019
- microsoft windows server 2019 (server core installation)
- microsoft windows server 2022
- microsoft windows server 2022, 23h2 edition (server core installation)
- microsoft windows server 2025
- microsoft windows server 2025 (server core installation)
- microsoft windows 10 1607
- microsoft windows 10 1809
- microsoft windows 10 21h2
- microsoft windows 10 22h2
- microsoft windows 11 23h2
- microsoft windows 11 24h2
- microsoft windows 11 25h2
- microsoft windows server 2012
- microsoft windows server 2022 23h2
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-21249 is a low vulnerability (CVSS 3.3) in Microsoft Windows 10 Version 1607, published February 10, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 11.3%, the 96th percentile. No source names a fixed version.