CVE-2026-107845 (GCVE-0-2026-107845)
Vulnerability from cvelistv5
Published
2026-10-09 19:29
Modified
2026-10-09 19:51
Severity ?
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-116 - Improper Encoding or Escaping of Output
Summary
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 Unpublished comments remain visible to moderators, so moderation does not prevent exposure.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.
Impacted products
Vendor Product Version
contao contao Version: >= 4.0.0, < 5.3.50
Version: >= 5.4.0-RC1, < 5.7.12
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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