{"id":"CVE-2026-49209","aliases":["EUVD-2026-45208","GHSA-mm82-c99c-h2cf"],"status":"published","title":"Symfony UX: Denial of service in symfony/ux-live-component via unbounded batch action requests","description":"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.","severity":{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.0056,"percentile":0.46972,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-770"],"published":"2026-06-19T19:34:45Z","modified":"2026-10-28T02:30:46Z","fixes":[{"ecosystem":"Packagist","package":"symfony/ux-live-component","fixed_in":["2.36.0","3.1.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Packagist","package":"symfony/ux-live-component","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.5.0"},{"fixed":"2.36.0"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/ux-live-component","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.0.0"},{"fixed":"3.1.0"}]}]},{"source":"osv","ecosystem":"Packagist","package":"symfony/ux-live-component","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.5.0"},{"fixed":"2.36.0"}]}],"versions":["v2.10.0","v2.11.0","v2.11.1","v2.11.2","v2.12.0","v2.13.0","v2.13.1","v2.13.2","v2.13.3","v2.14.0","v2.14.1","v2.14.2","v2.15.0","v2.16.0","v2.17.0","v2.18.0","v2.18.1","v2.19.0","v2.19.2","v2.20.0","v2.21.0","v2.22.0","v2.22.1","v2.23.0","v2.24.0","v2.25.0","v2.25.1","v2.25.2","v2.26.0","v2.26.1","v2.27.0","v2.28.0","v2.28.1","v2.28.2","v2.29.0","v2.29.1","v2.29.2","v2.30.0","v2.31.0","v2.32.0","v2.33.0","v2.34.0","v2.35.0","v2.5.0","v2.6.0","v2.6.1","v2.7.0","v2.7.1","v2.8.0","v2.8.1","v2.9.0","v2.9.1"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/ux-live-component","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.0.0"},{"fixed":"3.1.0"}]}],"versions":["v3.0.0"]}],"products":[{"vendor":"symfony","product":"ux"}],"references":[{"url":"https://github.com/symfony/ux/security/advisories/GHSA-mm82-c99c-h2cf","tags":["x_refsource_CONFIRM","Vendor Advisory","advisory","web"]},{"url":"https://github.com/symfony/ux/commit/95e878d5257f13d6d652ca95e3ef6bb0934d674f","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/symfony/ux/releases/tag/v2.36.0","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://github.com/symfony/ux/releases/tag/v3.1.0","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/ux-live-component/CVE-2026-49209.yaml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-mm82-c99c-h2cf"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49209.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49209","tags":["advisory"]},{"url":"https://github.com/symfony/ux","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-49209","title":"Symfony UX: Denial of service in symfony/ux-live-component via unbounded batch action requests","description":"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.","status":"published","published":"2026-07-17T16:02:06.498Z","modified":"2026-07-17T17:26:18.929Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T13:35:10.963527Z"}],"euvd":[{"id":"EUVD-2026-45208","description":"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.","status":"published","published":"2026-07-17T16:02:06Z","modified":"2026-07-17T17:26:18Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T18:19:50.451546Z"}],"ghsa":[{"id":"GHSA-mm82-c99c-h2cf","title":"symfony/ux-live-component: Denial of service via unbounded batch action requests","description":"### Description\n\n`Symfony\\UX\\LiveComponent\\Controller\\BatchActionController::__invoke()` iterates over the client-supplied `actions` array and issues a full `HttpKernel` sub-request for each entry (event subscribers, validators, Doctrine, rendering). The array size is never bounded, so an authenticated client can submit a single `_batch` request containing thousands of actions and exhaust CPU, memory, and database connections on the application server.\n\n### Resolution\n\n`BatchActionController` now enforces an upper bound of 50 actions per `_batch` request (`MAX_ACTIONS_PER_BATCH`) and rejects larger payloads up front with a `BadRequestHttpException`. The matching JavaScript backend was also updated to split larger client-side batches into multiple requests so legitimate usage isn't affected.\n\nThe patch for this issue is available [here](https://github.com/symfony/ux/commit/95e878d5257f13d6d652ca95e3ef6bb0934d674f) for branch 2.x (and forward-ported to 3.x).\n\n### Credits\n\nSymfony would like to thank Pascal Cescon for reporting the issue and Hugo Alliaume for providing the fix.","status":"published","published":"2026-06-19T19:34:45Z","modified":"2026-06-19T19:34:46Z","cvss":[{"version":"4.0","score":1.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U","level":"low"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:40:30.53004Z"}],"nvd":[{"id":"CVE-2026-49209","description":"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.","status":"published","published":"2026-07-17T17:17:15.517Z","modified":"2026-10-24T20:10:00.137Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:12:30.250437Z"}],"osv":[{"id":"CVE-2026-49209","title":"Symfony UX: Denial of service in symfony/ux-live-component via unbounded batch action requests","description":"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.","status":"published","published":"2026-07-17T16:02:06.498Z","modified":"2026-10-28T02:30:46.172143297Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:45:07.060148Z"},{"id":"GHSA-mm82-c99c-h2cf","title":"symfony/ux-live-component: Denial of service via unbounded batch action requests","description":"### Description\n\n`Symfony\\UX\\LiveComponent\\Controller\\BatchActionController::__invoke()` iterates over the client-supplied `actions` array and issues a full `HttpKernel` sub-request for each entry (event subscribers, validators, Doctrine, rendering). The array size is never bounded, so an authenticated client can submit a single `_batch` request containing thousands of actions and exhaust CPU, memory, and database connections on the application server.\n\n### Resolution\n\n`BatchActionController` now enforces an upper bound of 50 actions per `_batch` request (`MAX_ACTIONS_PER_BATCH`) and rejects larger payloads up front with a `BadRequestHttpException`. The matching JavaScript backend was also updated to split larger client-side batches into multiple requests so legitimate usage isn't affected.\n\nThe patch for this issue is available [here](https://github.com/symfony/ux/commit/95e878d5257f13d6d652ca95e3ef6bb0934d674f) for branch 2.x (and forward-ported to 3.x).\n\n### Credits\n\nSymfony would like to thank Pascal Cescon for reporting the issue and Hugo Alliaume for providing the fix.","status":"published","published":"2026-06-19T19:34:45Z","modified":"2026-09-10T03:51:09.083031592Z","cvss":[{"version":"4.0","score":1.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U","level":"low"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:46:52.170928Z"}]}}