CVE-2019-1166

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, aka 'Windows NTLM Tampering Vulnerability'.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.37% Top 20%
Vendor Advisory microsoft.com
Affected: Microsoft Windows
Affected: Microsoft Windows Server
Affected: Microsoft Windows 10 Version 1903 for 32-bit Systems
Affected: Microsoft Windows 10 Version 1903 for x64-based Systems
Affected: Microsoft Windows 10 Version 1903 for ARM64-based Systems
Affected: Microsoft Windows Server, version 1903 (Server Core installation)
Published at:
Updated at:

References

Link Tags
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1166 patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2019-1166?
CVE-2019-1166 has been scored as a medium severity vulnerability.
How to fix CVE-2019-1166?
To fix CVE-2019-1166, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-1166 being actively exploited in the wild?
It is possible that CVE-2019-1166 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-1166?
CVE-2019-1166 affects 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).
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