CVE-2019-1338

CVE-2019-1338 is a medium-severity vulnerability in Microsoft Windows 7 with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

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'.

Frequently asked questions

What is CVE-2019-1338?
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'.
How severe is CVE-2019-1338?
CVE-2019-1338 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2019-1338 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-1338?
CVE-2019-1338 primarily affects Microsoft Windows 7. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-1338?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-1338 published?
CVE-2019-1338 was published on 2019-10-10 and last updated on 2026-06-17.

References

Affected products (4)

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