Contao: Cross-site scripting in the comments bundle (contao contao)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.28 % · percentile 20 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Deferred
Description
Contao is an Open Source CMS. From version 4.0.0 until 5.3.50 and 5.7.12, an unauthenticated visitor can submit a comment whose email or website metadata is rendered without sufficient attribute and URL encoding by listComments() in comments-bundle/contao/dca/tl_comments.php. When a backend user opens the Comments module, attacker-controlled script can execute in the Contao backend origin under that user's session. Unpublished comments remain visible to moderators, so moderation does not prevent exposure. This issue is fixed in versions 5.3.50 and 5.7.12.
Weaknesses (CWE)
- CWE-79 — Improper Neutralization of Input During Web Page Generation
- CWE-116 — Improper Encoding or Escaping of Output
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | CRITICAL 9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N | GitHub_M |
| CVSS 3.1 | CRITICAL 9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-628f-v4f6-p37r — Contao: Cross-site scripting in the comments bundle
European references
- ENISA EUVD · EUVD-2026-95975
- GCVE · GCVE-0-2026-107845
Affected products
| Product | Versions |
|---|---|
| contao · contao | affected >= 4.0.0, < 5.3.50 ; affected >= 5.4.0-RC1, < 5.7.12 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |