CVE-2026-21249
LOWCVSS 3.3/10EPSS 11.36%
Last modified
CVE-2026-21249 is a low-severity vulnerability rated 3.3/10 on the CVSS scale. External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.. EPSS estimates a 11.36% chance of exploitation in the next 30 days.
Description
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
Metrics
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 10 1607 | < 10.0.14393.8868 |
| Microsoft | Windows 10 1809 | < 10.0.17763.8389 |
| Microsoft | Windows 10 21h2 | < 10.0.19044.6937 |
| Microsoft | Windows 10 22h2 | < 10.0.19045.6937 |
| Microsoft | Windows 11 23h2 | < 10.0.22631.6649 |
| Microsoft | Windows 11 24h2 | < 10.0.26100.7781 |
| Microsoft | Windows 11 25h2 | < 10.0.26200.7781 |
| Microsoft | Windows Server 2012 | r2 |
| Microsoft | Windows Server 2016 | < 10.0.14393.8868 |
| Microsoft | Windows Server 2019 | < 10.0.17763.8389 |
| Microsoft | Windows Server 2022 | < 10.0.20348.4711 |
| Microsoft | Windows Server 2022 23h2 | < 10.0.25398.2149 |
| Microsoft | Windows Server 2025 | < 10.0.26100.32313 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-21249?
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing locally.
How severe is CVE-2026-21249?
CVE-2026-21249 has a CVSS score of 3.3/10 (LOW severity). The EPSS model estimates a 11.36% probability of exploitation in the next 30 days.
How do I fix CVE-2026-21249?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
Are you affected by CVE-2026-21249?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST