CVE-2026-107845
criticalContao is an Open Source CMS.
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 Unpublished comments remain visible to moderators, so moderation does not prevent exposure.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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/contao/contao/commit/22505d5f79bc1a7f52e2cba5fddf6007e1f0408a security-advisories@github.com
- https://github.com/contao/contao/releases/tag/5.3.50 security-advisories@github.com
- https://github.com/contao/contao/releases/tag/5.7.12 security-advisories@github.com
- https://github.com/contao/contao/security/advisories/GHSA-628f-v4f6-p37r security-advisories@github.com