CVE-2019-1338
A security feature bypass vulnerability exists in Microsoft Windows when a man-in-the-middle...
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'.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
5.9
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'.
- Record
CVE-2019-1338- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Updated
- 2026-11-02
CVE List No score
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'.
- Record
CVE-2019-1338- Updated
- 2026-11-02
EUVDEUVD-2019-9896 No score
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'.
- Record
EUVD-2019-9896- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qm7q-vxj7-9xg3 No score
A security feature bypass vulnerability exists in Microsoft Windows when a man-in-the-middle...
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'.
- Record
GHSA-qm7q-vxj7-9xg3- Weakness
- CWE-326
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-1338 is a medium vulnerability (CVSS 5.9) in Microsoft Windows, published October 10, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.55%, the 89th percentile. No source names a fixed version.