- 5.3MediumCVSS base score
- 48.0%Exploitation in 30 daysEPSS · top 1.1% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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. An attacker who successfully exploited this vulnerability could gain the ability to downgrade NTLM security features. To exploit this vulnerability, the attacker would need to tamper with the NTLM exchange. The attacker could then modify flags of the NTLM packet without invalidating the signature. The update addresses the vulnerability by hardening NTLM MIC protection on the server-side.
Timeline
ID reserved
By microsoft
- 7 months later
· 7 months later
Published
- 6 years later
· 6 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| microsoftCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N/E:P/RL:O/RC:C |
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N |
- EPSS (exploitation in 30 days)
- 48.0% · top 1.1% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Affected products
Microsoft · Windows 10 Version 1703
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1803
- affected 10.0.0 – < publication
Microsoft · Windows Server, version 1803 (Server Core Installation)
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1809
- affected 10.0.17763.0 – < publication
Microsoft · Windows 10 Version 1809
- affected 10.0.0 – < publication
Microsoft · Windows Server 2019
- affected 10.0.17763.0 – < publication
Microsoft · Windows Server 2019 (Server Core installation)
- affected 10.0.17763.0 – < publication
Microsoft · Windows 10 Version 1709 for 32-bit Systems
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1709
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1903 for 32-bit Systems
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1903 for x64-based Systems
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1903 for ARM64-based Systems
- affected 10.0.0 – < publication
Microsoft · Windows Server, version 1903 (Server Core installation)
- affected 10.0.0 – < publication
Microsoft · Windows 10 Version 1507
- affected 10.0.10240.0 – < publication
Microsoft · Windows 10 Version 1607
- affected 10.0.14393.0 – < publication
Microsoft · Windows Server 2016
- affected 10.0.14393.0 – < publication
Microsoft · Windows Server 2016 (Server Core installation)
- affected 10.0.14393.0 – < publication
- affected 6.1.0 – < publication
Microsoft · Windows 7 Service Pack 1
- affected 6.1.0 – < publication
- affected 6.3.0 – < publication
Microsoft · Windows Server 2008 Service Pack 2
- affected 6.0.6003.0 – < publication
Microsoft · Windows Server 2008 Service Pack 2 (Server Core installation)
- affected 6.0.6003.0 – < publication
Microsoft · Windows Server 2008 Service Pack 2
- affected 6.0.0 – < publication
Microsoft · Windows Server 2008 Service Pack 2
- affected 6.0.6003.0 – < publication
Microsoft · Windows Server 2008 R2 Systems Service Pack 1
- affected 6.1.0 – < publication
Microsoft · Windows Server 2008 R2 Service Pack 1
- affected 6.1.7601.0 – < publication
Microsoft · Windows Server 2008 R2 Service Pack 1 (Server Core installation)
- affected 6.1.7601.0 – < publication
Microsoft · Windows Server 2012
- affected 6.2.9200.0 – < publication
Microsoft · Windows Server 2012 (Server Core installation)
- affected 6.2.9200.0 – < publication
Microsoft · Windows Server 2012 R2
- affected 6.3.9600.0 – < publication
Microsoft · Windows Server 2012 R2 (Server Core installation)
- affected 6.3.9600.0 – < publication
References
References2
- Windows NTLM Tampering Vulnerability (opens in a new tab)vendor-advisory
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1040 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2019-9625 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2019-1040)Record last updated .