{"id":"CVE-2026-35544","aliases":["DEBIAN-CVE-2026-35544","EUVD-2026-18591","GHSA-xpqh-grpw-4xmg","UBUNTU-CVE-2026-35544"],"status":"published","title":"Roundcube Webmail: Insufficient CSS sanitization in HTML e-mail messages","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of 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product":"webmail"},{"vendor":"roundcube","product":"webmail"}],"references":[{"url":"https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14","tags":["Vendor Advisory","web","report"]},{"url":"https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5","tags":["Release Notes","web","report"]},{"url":"https://github.com/roundcube/roundcubemail/commit/226811a1c974271dbedca72672923abaff8191c0","tags":["Patch","fix","web","report"]},{"url":"https://github.com/roundcube/roundcubemail/releases/tag/1.6.14","tags":["Release Notes","web","report"]},{"url":"https://github.com/roundcube/roundcubemail/commit/099009b9c8e1d3c636fb9a5af72f7c2596018662","tags":["Patch","fix","web","report"]},{"url":"https://github.com/roundcube/roundcubemail/releases/tag/1.5.14","tags":["Release Notes","web","report"]},{"url":"https://github.com/roundcube/roundcubemail/commit/57dec0c127b98e0c8e3b9c26c80049b9c4bcaea7","tags":["Patch","fix","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-35544","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-xpqh-grpw-4xmg"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35544.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-35544","tags":["advisory"]},{"url":"https://github.com/roundcube/roundcubemail","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-35544","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-35544","tags":["report"]},{"url":"https://nullcathedral.com/posts/2026-03-18-roundcube-round-two-three-more-sanitizer-bypasses/#css-position-fixed-important","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-35544","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T03:59:49.053Z","modified":"2026-04-03T12:50:12.338Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-669"],"updated_at":"2026-11-02T14:20:05.15083Z"}],"euvd":[{"id":"EUVD-2026-18591","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. 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Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T06:31:32Z","modified":"2026-04-04T06:57:39Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-669"],"updated_at":"2026-11-02T14:39:47.945242Z"}],"nvd":[{"id":"CVE-2026-35544","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T05:16:22.81Z","modified":"2026-07-24T21:10:00.143Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-669"],"updated_at":"2026-11-02T14:12:12.73929Z"}],"osv":[{"id":"CVE-2026-35544","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T03:59:49.053Z","modified":"2026-10-28T02:30:48.707474592Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-669"],"updated_at":"2026-11-02T15:45:02.673625Z"},{"id":"DEBIAN-CVE-2026-35544","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T05:16:22.81Z","modified":"2026-10-01T03:02:39.14047107Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:54.587575Z"},{"id":"GHSA-xpqh-grpw-4xmg","title":"Roundcube Webmail: Insufficient CSS sanitization in HTML e-mail messages","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T06:31:32Z","modified":"2026-04-04T07:11:22.193001Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-669"],"updated_at":"2026-11-02T15:47:00.198893Z"},{"id":"UBUNTU-CVE-2026-35544","description":"An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.","status":"published","published":"2026-04-03T05:16:00Z","modified":"2026-10-17T12:55:43.543655769Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T16:56:16.686388Z"}]}}