CVE-2026-15747

Mojolicious versions from 4.59 before 9.48 for Perl expose a stable representation of the session CSRF token to a BREACH compression oracle. _csrf_token generates and caches one token per session and returns the same value on every call, and _csrf_field places that value in a hidden `csrf_token` input. When a response carrying the token also echoes attacker-controlled input and is gzip-compressed, the chosen values and the resulting compressed lengths form a BREACH oracle. An attacker able to query it can recover the token and pass csrf_protect validation.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/mojolicious/mojo/commit/01921fbbbbeca2d1397e082d4a647f9b84c24e27.patch
https://metacpan.org/release/SRI/Mojolicious-9.48/changes
http://www.openwall.com/lists/oss-security/2026/07/14/16

Configurations

No configuration.

History

24 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Las versiones de Mojolicious desde la 4.59 anteriores a la 9.48 para Perl exponen una representación estable del token CSRF de la sesión a un oráculo de compresión BREACH. _csrf_token genera y almacena en caché un token por sesión y devuelve el mismo valor en cada llamada, y _csrf_field coloca ese valor en un campo de entrada oculto ’csrf_token’. Cuando una respuesta que lleva el token también hace eco de entrada controlada por el atacante y está comprimida con gzip, los valores elegidos y las longitudes comprimidas resultantes forman un oráculo BREACH. Un atacante capaz de consultarlo puede recuperar el token y pasar la validación de csrf_protect.

Information

Published : 2026-07-14 18:17

Updated : 2026-10-24 21:10

NVD link : CVE-2026-15747

Mitre link : CVE-2026-15747

CVE.ORG link : CVE-2026-15747

JSON object : View

Products Affected

No product.

CWE

CWE-204

Observable Response Discrepancy

CWE-352

Cross-Site Request Forgery (CSRF)

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