CVE-2026-77568

Medium CVSS 4.2

Published 2026-09-18 · last changed 2026-09-18

The fix

We hold no Microsoft remediation data for CVE-2026-77568, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.

What it is

Mojolicious is a real-time web framework for Perl. Prior to 9.48, the Mojolicious CSRF helpers csrf_field, csrf_token, and csrf_protect reuse an unchanged per-session token in rendered HTML. When response compression is enabled and attacker-influenced content is reflected in the same response, an unauthenticated attacker who can induce many victim requests and observe response sizes can use a BREACH compression side channel to recover the token and forge cross-site requests. API-only deployments that never render the token in HTML are not affected. This issue is fixed in version 9.48.

Sources

NVD record for CVE-2026-77568

CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N