{"id":"GHSA-g8wr-r2v2-vqc6","summary":"silverstripe/userforms vulnerable to remote code execution via userforms email subject","details":"### Impact\nThe userform email subject field in the CMS is vulnerable to a specially crafted payload being used to run arbitrary code on the server.\n\n### Reported by\nJack Wallace from Bastion Security","aliases":["CVE-2026-54721"],"modified":"2026-08-27T17:10:36.914600Z","published":"2026-08-27T16:53:17Z","database_specific":{"cwe_ids":["CWE-20","CWE-94"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2026-08-27T16:53:17Z","nvd_published_at":null},"references":[{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/security/advisories/GHSA-g8wr-r2v2-vqc6"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/pull/1441"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/pull/1442"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/commit/23c069866900c19b499bfa997d1e251e97491702"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/commit/c55494ad7c717b199a3c1663b43a54db5d95604c"},{"type":"WEB","url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/silverstripe/userforms/CVE-2026-54721.yaml"},{"type":"PACKAGE","url":"https://github.com/silverstripe/silverstripe-userforms"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/releases/tag/6.4.9"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/releases/tag/7.0.7"},{"type":"WEB","url":"https://github.com/silverstripe/silverstripe-userforms/releases/tag/7.1.1"},{"type":"WEB","url":"https://www.silverstripe.org/download/security-releases/cve-2026-54721"}],"affected":[{"package":{"name":"silverstripe/userforms","ecosystem":"Packagist","purl":"pkg:composer/silverstripe/userforms"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.9"}]}],"versions":["0.5.1","1.0.1","1.1.0-beta","2.0.1","2.0.1-rc1","2.0.10","2.0.2","2.0.3","2.0.4","2.0.5","2.0.6","2.0.7","2.0.8","2.0.9","3.0.0","3.0.0-beta1","3.0.1","3.0.2","3.1.0","3.1.1","3.1.2","4.0.0","4.0.1","4.1.0","4.2.0","4.2.1","4.2.2","4.2.3","4.2.4","4.2.5","4.2.6","4.3.0","4.3.1","4.3.2","4.3.3","4.3.4","4.3.5","4.4.0","4.4.1","4.4.2","4.5.0","4.5.1","4.5.2","4.5.3","4.5.4","4.5.5","4.5.6","4.5.7","4.5.8","4.6.0","4.6.1","4.6.2","4.6.3","5.0.0","5.0.0-beta1","5.0.0-beta2","5.0.1","5.0.2","5.1.0","5.1.1","5.10.0","5.10.0-alpha1","5.10.0-beta1","5.10.0-rc1","5.11.0","5.11.1","5.12.0","5.12.1","5.12.2","5.13.0","5.13.0-beta1","5.13.0-rc1","5.13.1","5.13.2","5.13.3","5.13.4","5.14.0","5.14.0-beta1","5.14.0-rc1","5.14.1","5.14.2","5.14.3","5.15.0","5.15.0-beta1","5.15.0-rc1","5.15.1","5.15.10","5.15.11","5.15.2","5.15.3","5.15.4","5.15.5","5.15.6","5.15.7","5.15.8","5.15.9","5.2.0","5.2.1","5.2.2","5.3.0","5.3.1","5.3.2","5.3.3","5.4.0","5.4.1","5.4.2","5.4.3","5.5.0","5.5.1","5.5.2","5.5.3","5.6.0","5.6.0-rc1","5.6.1","5.6.2","5.6.3","5.7.0","5.7.1","5.8.0","5.8.1","5.8.2","5.8.3","5.9.0","5.9.0-beta1","5.9.0-rc1","5.9.1","6.0.0","6.0.0-beta1","6.0.0-rc1","6.0.1","6.0.2","6.0.3","6.0.4","6.0.5","6.0.6","6.0.7","6.0.8","6.1.0","6.1.0-beta1","6.1.0-rc1","6.1.1","6.1.2","6.2.0","6.2.0-beta1","6.2.0-rc1","6.2.1","6.2.10","6.2.2","6.2.3","6.2.4","6.2.5","6.2.6","6.2.7","6.2.8","6.2.9","6.3.0","6.3.0-beta1","6.3.0-rc1","6.3.1","6.3.2","6.4.0","6.4.0-beta1","6.4.0-rc1","6.4.1","6.4.2","6.4.3","6.4.4","6.4.5","6.4.6","6.4.7","6.4.8","v5.9.2"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-g8wr-r2v2-vqc6/GHSA-g8wr-r2v2-vqc6.json"}},{"package":{"name":"silverstripe/userforms","ecosystem":"Packagist","purl":"pkg:composer/silverstripe/userforms"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.0.0"},{"fixed":"7.0.7"}]}],"versions":["7.0.0","7.0.1","7.0.2","7.0.3","7.0.4","7.0.5","7.0.6"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-g8wr-r2v2-vqc6/GHSA-g8wr-r2v2-vqc6.json"}},{"package":{"name":"silverstripe/userforms","ecosystem":"Packagist","purl":"pkg:composer/silverstripe/userforms"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.1.0"},{"fixed":"7.1.1"}]}],"versions":["7.1.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-g8wr-r2v2-vqc6/GHSA-g8wr-r2v2-vqc6.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}