Information Exposure Through Timing Discrepancy in WeeChat - CVE-2026-53525
Published: September 8, 2026
Vulnerability identifier: #VU147386
CSH Severity: Medium
CVSS v4: 8.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-53525
CWE-ID: CWE-208
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass authentication.
The vulnerability exists due to observable timing discrepancies in relay authentication password comparisons when processing authentication attempts. A remote attacker can measure response times for crafted authentication attempts to derive an expected hash and bypass authentication.
SHA- and PBKDF2-based authentication variants are affected, as is plaintext authentication when enabled.
Affected software
WeeChat
How to mitigate CVE-2026-53525
Install security update from vendor's website.
WeeChat - update to 4.9.1