{"id":"CVE-2026-107845","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-107845","generatedAt":"2026-10-28T01:01:29.816Z","title":"When a backend user opens the Comments module, attacker-controlled script can execute in the Contao backend origin under that user's session.","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 Unpublished comments remain visible to moderators, so moderation does not prevent exposure.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.","published":"2026-10-09T20:17:10.000Z","lastModified":"2026-10-16T17:17:04.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":9.3,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N"},"cwe":["CWE-79","CWE-116"],"affected":[],"epss":{"score":0.00277,"percentile":0.19971,"date":"2026-10-26","history":[{"date":"2026-10-10","score":0.00272,"percentile":0.17978}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-09T20:17:10.000Z","detail":{"score":"9.3","severity":"CRITICAL","publishedAt":"2026-10-09T20:17:10.457Z"},"summary":"New CVE, critical severity (CVSS 9.3)."}],"references":[{"url":"https://github.com/contao/contao/commit/22505d5f79bc1a7f52e2cba5fddf6007e1f0408a","source":"security-advisories@github.com"},{"url":"https://github.com/contao/contao/releases/tag/5.3.50","source":"security-advisories@github.com"},{"url":"https://github.com/contao/contao/releases/tag/5.7.12","source":"security-advisories@github.com"},{"url":"https://github.com/contao/contao/security/advisories/GHSA-628f-v4f6-p37r","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-107845","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}