Rapid7

vulnerability

Red Hat: CVE-2017-2624: xorg-x11-server: timing attack against MIT Cookie

Severity
2
CVSS
(AV:L/AC:M/Au:N/C:P/I:N/A:N)
Published
Jul 27, 2018
Added
Jul 9, 2025
Modified
Jul 9, 2025

Description

It was found that xorg-x11-server before 1.19.0 including uses memcmp() to check the received MIT cookie against a series of valid cookies. If the cookie is correct, it is allowed to attach to the Xorg session. Since most memcmp() implementations return after an invalid byte is seen, this causes a time difference between a valid and invalid byte, which could allow an efficient brute force attack.

Solution

no-fix-redhat-rpm-package
Title
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