Vulnerability in Microsoft Windows 10

CVE-2019-1040

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.

EPSS: 0.480 (98.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N.

Affected products

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2019-1040?
CVE-2019-1040 is a medium-severity vulnerability in Microsoft Windows 10. CVSS score: 5.3/10. Published 2019-06-12.
How severe is CVE-2019-1040?
Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2019-1040 known to be exploited?
113 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.