{"id":"CVE-2026-49209","aliases":["GHSA-mm82-c99c-h2cf"],"url":"https://o3.security/vulnerability/CVE-2026-49209","summary":"Symfony UX: Denial of service in symfony/ux-live-component via unbounded batch action requests","details":"Symfony UX is a JavaScript ecosystem for Symfony. From 2.5.0 until 2.36.0 and 3.1.0, Symfony\\UX\\LiveComponent\\Controller\\BatchActionController::__invoke() iterates over the client-supplied actions array and issues a full HttpKernel sub-request for each entry; because the array size is never bounded, an authenticated client can submit a single _batch request containing thousands of actions and exhaust CPU, memory, and database connections on the application server. This issue is fixed in versions 2.36.0 and 3.1.0.","published":"2026-07-17T16:02:06.498Z","modified":"2026-08-12T03:51:22.975763868Z","cvss":null,"epss":{"score":0.0056,"percentile":0.44891,"asOf":"2026-09-13"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"symfony/ux-live-component","fixedVersion":"2.36.0"},{"ecosystem":"Packagist","name":"symfony/ux-live-component","fixedVersion":"3.1.0"}],"fix":{"url":"https://github.com/symfony/ux/commit/95e878d5257f13d6d652ca95e3ef6bb0934d674f","label":"symfony/ux@95e878d"},"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-2026-49209.json"},{"type":"ADVISORY","url":"https://github.com/symfony/ux/security/advisories/GHSA-mm82-c99c-h2cf"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49209"},{"type":"FIX","url":"https://github.com/symfony/ux/commit/95e878d5257f13d6d652ca95e3ef6bb0934d674f"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:22.975763868Z"}}