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.
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Tue, 20 May 2025 18:00:00 +0000
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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'. | 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. |
Title | Windows NTLM Tampering Vulnerability | |
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cvssV3_1
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Status: PUBLISHED
Assigner: microsoft
Published: 2019-06-12T13:49:40
Updated: 2025-05-20T17:50:16.225Z
Reserved: 2018-11-26T00:00:00
Link: CVE-2019-1040

No data.

Status : Modified
Published: 2019-06-12T14:29:03.713
Modified: 2025-05-20T18:15:39.637
Link: CVE-2019-1040

No data.