---
id: CVE-2026-53525
title: WeeChat (Wee Enhanced Environment for Chat) is a free chat client
summary: >-
  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
  ha…
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H'
cwe:
  - CWE-208
published: '2026-08-21'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T21:06:39.057'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53525'
references:
  - url: 'https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc'
    label: security-advisories@github.com
  - url: 'https://github.com/weechat/weechat/security/advisories/GHSA-vhv8-g2r9-cwcc'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00432
epssPercentile: 0.34781
ingestedAt: '2026-09-09T21:22:45.549Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.