{"id":"CVE-2026-49210","summary":"Symfony UX: XSS in symfony/ux-live-component via attacker-controlled child component tag","details":"Symfony UX is a JavaScript ecosystem for Symfony. From 2.8.0 until 2.36.0 and 3.1.0, Symfony\\UX\\LiveComponent\\Util\\ChildComponentPartialRenderer::createHtml() interpolates the client-controlled children[id].tag value from LiveComponentSubscriber and InterceptChildComponentRenderSubscriber directly into HTML as a tag name without escaping or validation, allowing arbitrary HTML, including \u003cscript\u003e tags, on any Live Component re-render that contains at least one child component. This issue is fixed in versions 2.36.0 and 3.1.0.","aliases":["GHSA-38x5-rcv4-xf7x"],"modified":"2026-08-12T03:51:13.091750469Z","published":"2026-07-17T16:09:17.850Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-79"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49210.json"},"references":[{"type":"WEB","url":"https://github.com/symfony/ux/releases/tag/v2.36.0"},{"type":"WEB","url":"https://github.com/symfony/ux/releases/tag/v3.1.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49210.json"},{"type":"ADVISORY","url":"https://github.com/symfony/ux/security/advisories/GHSA-38x5-rcv4-xf7x"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49210"},{"type":"FIX","url":"https://github.com/symfony/ux/commit/fbc5e9a1bda7e4556be21bb1d970f382760ed9a9"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/symfony/ux","events":[{"introduced":"8e214d4461a62f78956607500d9417ddc2f451ef"},{"fixed":"5ccec9746faa28d79a87138042174c3853d5702b"},{"introduced":"3cef8e0d9557bbde60c3f1bfd2cbb1004af7fc9a"},{"fixed":"fbc5e9a1bda7e4556be21bb1d970f382760ed9a9"},{"fixed":"4c883fdb0f0e7ea577f851bd457024f7e88788c9"}],"database_specific":{"extracted_events":[{"introduced":"2.8.0"},{"fixed":"2.36.0"},{"introduced":"3.0.0"},{"last_affected":"3.0.0"}],"source":["CPE_RANGE","CPE_STRING","REFERENCES"],"cpe":["cpe:2.3:a:symfony:ux:*:*:*:*:*:*:*:*","cpe:2.3:a:symfony:ux:3.0.0:*:*:*:*:*:*:*"]}}],"versions":["3.0.0","v2.35.0","v3.0.0","v2.34.0","v2.33.0","v2.32.0","v2.31.0","v2.30.0","v2.29.2","v2.29.1","v2.29.0","v2.28.2","v2.28.1","v2.28.0","v2.27.0","v2.26.0","v2.26.1","v2.25.2","v2.25.1","v2.25.0","v2.24.0","v2.23.0","v2.22.1","v2.22.0","v2.21.0","v2.9.1","v2.20.0","v2.19.3","v2.19.2","v2.19.0","v2.19.1","v2.18.1","v2.18.0","v2.17.0","v2.16.0","v2.14.0","v2.15.0","v2.14.2","v2.14.1","v2.13.1","v2.13.3","v2.13.2","v2.13.0","v2.12.0","v2.11.1","v2.11.2","v2.11.0","v2.10.0","v2.8.1","v2.9.0","v2.8.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49210.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N"}]}