CVE-2026-53525

high

Description

WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 0.3.1 through 4.9.0, the WeeChat relay authentication uses non-constant-time string comparison functions (weechat_strcasecmp and strcmp) to verify password hashes and plaintext passwords. An attacker can exploit timing differences to extract the server-computed hash character by character, then authenticate using the correct hash without knowing the password. Version 4.9.1 fixes the issue.

References

https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc

Details

Source: Mitre, NVD

Published: 2026-08-21

Updated: 2026-08-21

Risk Information

CVSS v2

Base Score: 7.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:C/A:C

Severity: High

CVSS v3

Base Score: 7.4

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H

Severity: High

EPSS

EPSS: 0.00432