CVE-2019-1166 json
A tampering vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLM MIC (Messag…
published 2019-10-10 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-9738
- cvss
- 5.9
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 68.1%
- EPSS 68.1% chance of exploitation in 30 days, percentile 99.3%
- public exploits
- 0
- none known
Summary
A tampering vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLM MIC (Message Integrity Check) protection, aka 'Windows NTLM Tampering Vulnerability'.
Patch / fix
Exploit prediction
68.11% chance of exploitation in the next 30 days, higher than 99.3% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Affected products
- Microsoft Windows
- Microsoft Windows Server
- Microsoft Windows 10 Version 1903 for 32-bit Systems
- Microsoft Windows 10 Version 1903 for x64-based Systems
- Microsoft Windows 10 Version 1903 for ARM64-based Systems
- Microsoft Windows Server, version 1903 (Server Core installation)
Classification
- Weakness
-
- CWE-354 Improper Validation of Integrity Check Value
References
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2019-1166
patch, vendor-advisory
Sources
- CVE List CVE-2019-1166
- NVD CVE-2019-1166
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