VULNERABILITY INTELLIGENCE
CVE-2026-15747
CVSS score9.1 CRITICAL
EPSS probability0.25%
CISA KEVNot currently listed
Published2026-07-14
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Description
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.
Weakness classification
- 9b29abf9-4ab0-4765-b253-1875cd9b441e: CWE-204