{"answers":{"affected":"4 open source packages ship an affected version, including contao/comments-bundle.","exploited":"There is no known exploitation of CVE-2026-107845 in the wild and no public exploit code.","fix":"Upgrade contao/comments-bundle to a fixed version for your release line: 5.3.50 or 5.7.12.","what":"CVE-2026-107845 is a critical cross-site scripting vulnerability in contao, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-107845 and fix it if it is affected.\n\nWhat it is: CVE-2026-107845 is a critical cross-site scripting vulnerability in contao, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-107845 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- contao/comments-bundle (Packagist): affected from 4.0.0; fixed in 5.3.50\n- contao/comments-bundle (Packagist): affected from 4.0.0; fixed in 5.3.50\n- contao/comments-bundle (Packagist): affected from 5.4.0-RC1; fixed in 5.7.12\n- contao/comments-bundle (Packagist): affected from 5.4.0-RC1; fixed in 5.7.12\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-107845/ (Markdown: https://insights.sbomify.com/CVE-2026-107845/index.md)","id":"CVE-2026-107845","markdown":"https://insights.sbomify.com/CVE-2026-107845/index.md","name":"CVE-2026-107845","record":{"aliases":["GHSA-628f-v4f6-p37r"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["code_execution","account_takeover"],"network_reachable":"yes","non_default_config":false,"product_category":"Contao CMS","requires_auth":"none","summary":"An unauthenticated attacker can inject scripts via comment metadata that execute in the backend when moderators view comments, potentially leading to session hijacking.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":9.3,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"},{"id":"CWE-116","name":"Improper Encoding or Escaping of Output"}],"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.","ecosystems":["Packagist"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Contao: Cross-site scripting in the comments bundle","id":"CVE-2026-107845","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Packagist","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":4,"n_references":4,"next":{"headline":"Contao: Cross-site request forgery in custom backend actions","id":"CVE-2026-107848"},"packages":[{"ecosystem":"Packagist","fixed":["5.3.50"],"introduced":["4.0.0"],"last_affected":[],"package":"contao/comments-bundle","purl":null,"source":"GHSA-628f-v4f6-p37r"},{"ecosystem":"Packagist","fixed":["5.3.50"],"introduced":["4.0.0"],"last_affected":[],"package":"contao/comments-bundle","purl":"pkg:composer/contao/comments-bundle","source":"GHSA-628f-v4f6-p37r"},{"ecosystem":"Packagist","fixed":["5.7.12"],"introduced":["5.4.0-RC1"],"last_affected":[],"package":"contao/comments-bundle","purl":null,"source":"GHSA-628f-v4f6-p37r"},{"ecosystem":"Packagist","fixed":["5.7.12"],"introduced":["5.4.0-RC1"],"last_affected":[],"package":"contao/comments-bundle","purl":"pkg:composer/contao/comments-bundle","source":"GHSA-628f-v4f6-p37r"}],"prev":{"headline":"Contao: Path traversal in the images controller","id":"CVE-2026-107844"},"products":["contao"],"published":"2026-10-09","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-09","vendors":["contao"]},"summary":"An unauthenticated attacker can inject scripts via comment metadata that execute in the backend when moderators view comments, potentially leading to session hijacking.","url":"https://insights.sbomify.com/CVE-2026-107845/"}