{"id":"CVE-2026-33347","summary":"league/commonmark has an embed extension allowed_domains bypass","details":"league/commonmark is a PHP Markdown parser. From version 2.3.0 to before version 2.8.2, the DomainFilteringAdapter in the Embed extension is vulnerable to an allowlist bypass due to a missing hostname boundary assertion in the domain-matching regex. An attacker-controlled domain like youtube.com.evil passes the allowlist check when youtube.com is an allowed domain. This issue has been patched in version 2.8.2.","aliases":["GHSA-hh8v-hgvp-g3f5"],"modified":"2026-09-17T03:46:05.402637444Z","published":"2026-03-24T19:26:23.872Z","database_specific":{"unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"2.3.0"},{"fixed":"2.8.2"}]},{"extracted_events":[{"fixed":"2.8.2"}],"source":"DESCRIPTION"}],"cna_assigner":"GitHub_M","cwe_ids":["CWE-185","CWE-79","CWE-918"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33347.json"},"references":[{"type":"WEB","url":"https://github.com/thephpleague/commonmark/releases/tag/2.8.2"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33347.json"},{"type":"ADVISORY","url":"https://github.com/thephpleague/commonmark/security/advisories/GHSA-hh8v-hgvp-g3f5"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33347"},{"type":"FIX","url":"https://github.com/thephpleague/commonmark/commit/59fb075d2101740c337c7216e3f32b36c204218b"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/thephpleague/commonmark","events":[{"introduced":"0"},{"fixed":"59fb075d2101740c337c7216e3f32b36c204218b"}],"database_specific":{"source":"REFERENCES"}}],"versions":["2.8.1","2.8.0","2.7.0","2.6.0","2.5.0","2.4.0","2.3.0","2.2.0","2.1.0","2.0.2","2.0.1","2.0.0","2.0.0-rc2","2.0.0-rc1","2.0.0-beta3","2.0.0-beta2","2.0.0-beta1","0.18.1","0.17.4","0.17.2","0.17.0","0.16.0","0.15.7","0.15.6","0.15.5","0.15.4","0.15.3","0.15.2","0.15.1","0.15.0","0.14.0","0.13.4","0.13.3","0.13.2","0.13.1","0.13.0","0.12.0","0.11.3","0.11.2","0.11.1","0.11.0","0.10.0","0.9.0","0.8.0","0.7.1","0.7.0","0.6.1","0.6.0","0.5.1","0.5.0","0.4.0","0.3.0","0.2.1","0.2.0","0.1.2","0.1.1","0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-33347.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N"}]}