Mojolicious: CSRF tokens are vulnerable to BREACH attacks (CVE-2026-77568) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-77568

Mojolicious: CSRF tokens are vulnerable to BREACH attacks

Answer in brief

CVE-2026-77568 records a Unknown severity vulnerability in Mojolicious: CSRF tokens are vulnerable to BREACH attacks. The current sources do not mark it as known exploited. The current feed maps mojolicious/mojo (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 18, 2026Updated Sep 18, 2026Source checked Sep 18, 2026First seen by HOL Sep 18, 2026Material review Sep 18, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps mojolicious/mojo (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
mojolicious/mojogeneric	< 9.48	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for mojolicious/mojo.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 18, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 18, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.