CVE-2026-15747 Cross-site request forgery in Mojolicious
Attackers can recover CSRF tokens via compression oracles to bypass CSRF protection in Mojolicious applications using gzip compression.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-15747?
CVE-2026-15747 is a critical vulnerability in SRI Mojolicious, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-15747?
Linux distribution packages (3)
perl-Mojolicious SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 9.370.0-150700.3.3.1 |
perl-Mojolicious openSUSE:Leap 16.0 | All versions | 9.480.0-bp160.1.1 |
perl-Mojolicious openSUSE:Tumbleweed | All versions | 9.480.0-1.1 |
How do I fix CVE-2026-15747?
Upgrade to a fixed version.
Is CVE-2026-15747 being exploited?
There is no known exploitation of CVE-2026-15747 in the wild and no public exploit code.
Sources
Also known as AZL-92394, CVE-2026-77568, DEBIAN-CVE-2026-15747, GHSA-6cg9-7rr8-cvj2, MGASA-2026-0356, SUSE-SU-2026:4151-1 and 3 more.