CVE-2026-53525

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.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

No configuration.

History

14 Oct 2026, 19:10

Type	Values Removed	Values Added
Summary		(es) WeeChat (Wee Enhanced Environment for Chat) es un cliente de chat gratuito. En las versiones 0.3.1 a 4.9.0, la autenticación de retransmisión de WeeChat utiliza funciones de comparación de cadenas de tiempo no constante (weechat_strcasecmp y strcmp) para verificar los hashes de contraseña y las contraseñas en texto plano. Un atacante puede explotar las diferencias de tiempo para extraer el hash calculado por el servidor carácter por carácter, y luego autenticarse usando el hash correcto sin conocer la contraseña. La versión 4.9.1 corrige el problema.

Information

Published : 2026-08-21 23:16

Updated : 2026-10-14 19:10

NVD link : CVE-2026-53525

Mitre link : CVE-2026-53525

CVE.ORG link : CVE-2026-53525

JSON object : View

Products Affected

No product.

CWE

CWE-208

Observable Timing Discrepancy

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