{"id":"CVE-2026-41305","summary":"PostCSS has XSS via Unescaped \u003c/style\u003e in its CSS Stringify Output","details":"PostCSS takes a CSS file and provides an API to analyze and modify its rules by transforming the rules into an Abstract Syntax Tree. Versions prior to 8.5.10 do not escape `\u003c/style\u003e` sequences when stringifying CSS ASTs. When user-submitted CSS is parsed and re-stringified for embedding in HTML `\u003cstyle\u003e` tags, `\u003c/style\u003e` in CSS values breaks out of the style context, enabling XSS. Version 8.5.10 fixes the issue.","aliases":["GHSA-qx2v-qp2m-jg93"],"modified":"2026-06-18T03:55:35.411207358Z","published":"2026-04-24T02:27:47.719Z","related":["CGA-jr2c-rgcp-7w5j"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41305.json","cwe_ids":["CWE-79"],"cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/postcss/postcss/releases/tag/8.5.10"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41305.json"},{"type":"ADVISORY","url":"https://github.com/postcss/postcss/security/advisories/GHSA-qx2v-qp2m-jg93"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-41305"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/postcss/postcss","events":[{"introduced":"0"},{"fixed":"33b9790263dc1562a46ce45d9532bd63e95b7986"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"8.5.10"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["8.5.9","8.5.8","8.5.7","8.5.6","8.5.5","8.5.4","8.5.3","8.5.2","8.5.1","8.5.0","8.4.49","8.4.48","8.4.47","8.4.46","8.4.45","8.4.44","8.4.43","8.4.42","8.4.41","8.4.40","8.4.39","8.4.38","8.4.37","8.4.36","8.4.35","8.4.34","8.4.33","8.4.32","8.4.31","8.4.30","8.4.29","8.4.28","8.4.27","8.4.26","8.4.25","8.4.24","8.4.23","8.4.22","8.4.21","8.4.20","8.4.19","8.4.18","8.4.17","8.4.16","8.4.15","8.4.14","8.4.13","8.4.12","8.4.11","8.4.10","8.4.9","8.4.8","8.4.7","8.4.6","8.4.5","8.4.0","8.4.4","8.4.3","8.4.2","8.4.1","8.3.11","8.3.10","8.3.9","8.3.8","8.3.7","8.3.6","8.3.5","8.3.4","8.3.3","8.3.2","8.3.1","8.3.0","8.2.15","8.2.14","8.2.13","8.2.12","8.2.11","8.2.10","8.2.9","8.2.8","8.2.7","8.2.6","8.2.5","8.2.4","8.2.3","8.2.2","8.2.1","8.2.0","8.1.14","8.1.13","8.1.12","8.1.11","8.1.10","8.1.9","8.1.8","8.1.7","8.1.6","8.1.5","8.1.4","8.1.3","8.1.2","8.1.1","8.1.0","8.0.9","8.0.8","8.0.7","8.0.6","8.0.5","8.0.4","7.0.32","8.0.3","8.0.2","8.0.1","8.0.0","7.0.31","7.0.30","7.0.29","7.0.28","7.0.27","7.0.26","7.0.25","7.0.24","7.0.23","7.0.22","7.0.21","7.0.20","7.0.19","7.0.18","7.0.17","7.0.16","7.0.15","7.0.14","7.0.13","7.0.12","7.0.11","7.0.10","7.0.9","7.0.8","7.0.7","7.0.6","7.0.5","7.0.4","7.0.3","7.0.2","7.0.1","7.0.0","6.0.23","6.0.22","6.0.21","6.0.20","6.0.19","6.0.18","6.0.17","6.0.16","6.0.15","6.0.14","6.0.13","6.0.12","6.0.11","6.0.10","6.0.9","6.0.8","6.0.7","6.0.6","6.0.5","6.0.4","6.0.3","6.0.2","6.0.1","6.0.0","5.2.17","5.2.16","5.2.15","5.2.14","5.2.13","5.2.12","5.2.11","5.2.10","5.2.9","5.2.8","5.2.7","5.2.6","5.2.5","5.2.4","5.2.3","5.2.2","5.2.1","5.2.0","5.1.2","5.1.1","5.1.0","5.0.21","5.0.20","5.0.19","5.0.18","5.0.17","5.0.16","5.0.15","5.0.14","5.0.13","5.0.12","5.0.11","5.0.10","5.0.9","5.0.8","5.0.7","5.0.6","5.0.5","5.0.4","5.0.3","5.0.2","5.0.1","5.0.0","4.1.16","4.1.15","4.1.14","4.1.13","4.1.12","4.1.11","4.1.10","4.1.9","4.1.8","4.1.7","4.1.6","4.1.5","4.1.4","4.1.3","4.1.2","4.1.1","4.1.0","4.0.6","4.0.5","4.0.4","4.0.3","4.0.2","4.0.1","4.0.0","3.0.7","3.0.6","3.0.5","3.0.4","3.0.3","3.0.2","3.0.1","3.0.0","2.2.6","2.2.5","2.2.4","2.2.3","2.2.2","2.2.1","2.2.0","2.1.2","2.1.1","2.1.0","2.0.0","1.0.0","0.3.5","0.3.4","0.3.3","0.3.2","0.3.1","0.3","0.2","0.1"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-41305.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"}]}