A security feature bypass vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the…

Description

A security feature bypass vulnerability exists in Microsoft Windows when a man-in-the-middle attacker is able to successfully bypass the NTLMv2 protection if a client is also sending LMv2 responses, aka 'Windows NTLM Security Feature Bypass Vulnerability'.

Scores

EPSS (exploitation in 30 days)

3.6% · top 11% of all CVEs (6 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.

Weakness

• Security Feature Bypass

Affected products

• Microsoft · Windows

  • affected 7 for 32-bit Systems Service Pack 1
  • affected 7 for x64-based Systems Service Pack 1

• Microsoft · Windows Server

  • affected 2008 R2 for x64-based Systems Service Pack 1 (Core installation)
  • affected 2008 R2 for Itanium-Based Systems Service Pack 1
  • affected 2008 R2 for x64-based Systems Service Pack 1
  • affected 2008 for 32-bit Systems Service Pack 2 (Core installation)
  • affected 2008 for Itanium-Based Systems Service Pack 2
  • affected 2008 for 32-bit Systems Service Pack 2
  • affected 2008 for x64-based Systems Service Pack 2
  • affected 2008 for x64-based Systems Service Pack 2 (Core installation)

References (1)

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1338 (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)
• 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

[![CVE-2019-1338](https://trackcve.app/badge/CVE-2019-1338.svg)](https://trackcve.app/cve/CVE-2019-1338)

Record last updated 4 Aug 2024, 18:13 UTC.