{"id":"CVE-2026-45753","aliases":["GHSA-hhg7-c65m-h7ff"],"url":"https://o3.security/vulnerability/CVE-2026-45753","summary":"Symfony: HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — javascript: URI Survives Sanitization (XSS)","details":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","published":"2026-07-14T18:21:13.644Z","modified":"2026-08-12T03:51:24.151843640Z","cvss":null,"epss":{"score":0.00293,"percentile":0.21907,"asOf":"2026-08-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"symfony/html-sanitizer","fixedVersion":"6.4.40"},{"ecosystem":"Packagist","name":"symfony/html-sanitizer","fixedVersion":"7.4.12"},{"ecosystem":"Packagist","name":"symfony/html-sanitizer","fixedVersion":"8.0.12"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"6.4.40"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"7.4.12"},{"ecosystem":"Packagist","name":"symfony/symfony","fixedVersion":"8.0.12"}],"fix":{"url":"https://github.com/symfony/symfony/commit/487728e7e180a674a6d4c01bd0cb56161cc441b7","label":"symfony/symfony@487728e"},"references":[{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v6.4.40"},{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v7.4.12"},{"type":"WEB","url":"https://github.com/symfony/symfony/releases/tag/v8.0.12"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45753.json"},{"type":"ADVISORY","url":"https://github.com/symfony/symfony/security/advisories/GHSA-hhg7-c65m-h7ff"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45753"},{"type":"FIX","url":"https://github.com/symfony/symfony/commit/487728e7e180a674a6d4c01bd0cb56161cc441b7"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:24.151843640Z"}}