{"id":"UBUNTU-CVE-2026-33347","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.","modified":"2026-05-20T16:12:48.456224461Z","published":"2026-03-24T20:16:00Z","related":["USN-8194-1"],"upstream":["CVE-2026-33347"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-33347"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-33347"},{"type":"REPORT","url":"https://github.com/thephpleague/commonmark/security/advisories/GHSA-hh8v-hgvp-g3f5"},{"type":"REPORT","url":"https://github.com/thephpleague/commonmark/commit/59fb075d2101740c337c7216e3f32b36c204218b"},{"type":"REPORT","url":"https://github.com/thephpleague/commonmark/releases/tag/2.8.2"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8194-1"}],"affected":[{"package":{"name":"php-league-commonmark","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/php-league-commonmark?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.1-1ubuntu2+esm1"}]}],"versions":["1.1.2-1","1.2.0-1","1.3.0-1","1.3.1-1","1.3.1-1ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.1-1ubuntu2+esm1","binary_name":"php-league-commonmark"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33347.json"}},{"package":{"name":"php-league-commonmark","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/php-league-commonmark?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.7-1ubuntu0.1~esm1"}]}],"versions":["1.5.7-2build1","1.6.6-1build1","1.6.7-1"],"ecosystem_specific":{"binaries":[{"binary_name":"php-league-commonmark","binary_version":"1.6.7-1ubuntu0.1~esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33347.json"}},{"package":{"name":"php-league-commonmark","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/php-league-commonmark?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.4.2-2ubuntu0.1~esm1"}]}],"versions":["2.3.9-1","2.4.1-1","2.4.2-1","2.4.2-2"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"php-league-commonmark","binary_version":"2.4.2-2ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33347.json"}},{"package":{"name":"php-league-commonmark","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/php-league-commonmark?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.1-2","2.6.2-1","2.7.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"php-league-commonmark","binary_version":"2.7.0-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33347.json"}},{"package":{"name":"php-league-commonmark","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/php-league-commonmark?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.7.0-1","2.7.1-2","2.8.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"php-league-commonmark","binary_version":"2.8.0-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33347.json"}}],"schema_version":"1.7.5","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"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}