CVE-2019-1040

Windows NTLM Tampering Vulnerability

At a glance

Severity
MEDIUM 5.3
EPSS
EPSS 48.04 % · percentile 99 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
microsoft
NVD status
Modified

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.

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.3CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N/E:P/RL:O/RC:Cmicrosoft
CVSS 3.1MEDIUM 5.3CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:NNVD · secure@microsoft.com (Secondary)
CVSS 3.0MEDIUM 5.9CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NNVD · nvd@nist.gov (Secondary)
CVSS 2.0MEDIUM 4.3AV:N/AC:M/Au:N/C:N/I:P/A:NNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Microsoft · Windows 10 Version 1703affected 10.0.0 < publication
Microsoft · Windows 10 Version 1803affected 10.0.0 < publication
Microsoft · Windows Server, version 1803 (Server Core Installation)affected 10.0.0 < publication
Microsoft · Windows 10 Version 1809affected 10.0.17763.0 < publication
Microsoft · Windows 10 Version 1809affected 10.0.0 < publication
Microsoft · Windows Server 2019affected 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 Systemsaffected 10.0.0 < publication
Microsoft · Windows 10 Version 1709affected 10.0.0 < publication
Microsoft · Windows 10 Version 1903 for 32-bit Systemsaffected 10.0.0 < publication
Microsoft · Windows 10 Version 1903 for x64-based Systemsaffected 10.0.0 < publication
Microsoft · Windows 10 Version 1903 for ARM64-based Systemsaffected 10.0.0 < publication
Microsoft · Windows Server, version 1903 (Server Core installation)affected 10.0.0 < publication
Microsoft · Windows 10 Version 1507affected 10.0.10240.0 < publication
Microsoft · Windows 10 Version 1607affected 10.0.14393.0 < publication
Microsoft · Windows Server 2016affected 10.0.14393.0 < publication
Microsoft · Windows Server 2016 (Server Core installation)affected 10.0.14393.0 < publication
Microsoft · Windows 7affected 6.1.0 < publication
Microsoft · Windows 7 Service Pack 1affected 6.1.0 < publication
Microsoft · Windows 8.1affected 6.3.0 < publication

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD