{"id":"CVE-2021-26929","aliases":["DEBIAN-CVE-2021-26929","DLA-2564-1","EUVD-2021-13711","GHSA-qc5g-54hm-vfmc","UBUNTU-CVE-2021-26929"],"status":"published","title":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the...","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","severity":{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.05004,"percentile":0.92344,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":true},"cwes":["CWE-79"],"published":"2021-02-14T03:43:49Z","modified":"2026-10-24T10:50:11Z","exploits":[{"source":"exploitdb","id":"EDB-49769","title":"Horde Groupware Webmail 5.2.22 - Stored XSS","type":"webapps","platform":"multiple","date":"2021-04-15","url":"https://www.exploit-db.com/exploits/49769"}],"fixes":[{"ecosystem":"Debian:12","package":"php-horde-text-filter","fixed_in":["2.3.7-1"],"sources":["osv"]},{"ecosystem":"Debian:9","package":"php-horde-text-filter","fixed_in":["2.3.5-1+deb9u1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"php-horde-text-filter","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.7-1"}]}]},{"source":"osv","ecosystem":"Debian:9","package":"php-horde-text-filter","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.5-1+deb9u1"}]}],"versions":["2.3.5-1"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"php-horde-text-filter","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.3.2-1","2.3.2-2","2.3.3-1","2.3.3-1ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"php-horde-text-filter","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.3.5-1","2.3.5-1ubuntu1"]}],"products":[{"vendor":"debian","product":"debian_linux"},{"vendor":"horde","product":"groupware"}],"references":[{"url":"https://github.com/horde/webmail/releases","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","report"]},{"url":"https://www.horde.org/apps/webmail","tags":["x_refsource_MISC","x_transferred","Vendor Advisory","advisory","report"]},{"url":"https://www.alexbirnberg.com/horde-xss.html","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","evidence","report"]},{"url":"https://lists.horde.org/archives/announce/2021/001298.html","tags":["x_refsource_CONFIRM","x_transferred","Mailing List","Vendor Advisory","advisory","report"]},{"url":"https://lists.debian.org/debian-lts-announce/2021/02/msg00028.html","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"http://packetstormsecurity.com/files/162187/Webmail-Edition-5.2.22-XSS-Remote-Code-Execution.html","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","VDB Entry","evidence"]},{"url":"http://packetstormsecurity.com/files/162194/Horde-Groupware-Webmail-5.2.22-Cross-Site-Scripting.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-26929"},{"url":"https://github.com/advisories/GHSA-qc5g-54hm-vfmc"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-26929","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-26929","tags":["report"]},{"url":"https://github.com/horde/Text_Filter/commit/c26f938854c36b981558a3b1b9b2f81403cff60e","tags":["report"]},{"url":"https://github.com/horde/Text_Filter/commit/a2f67da064d7a91440b7a2448e56a6387ab94c67","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-26929","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-26929","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2021-02-14T03:43:49Z","modified":"2024-08-03T20:33:41.62Z","updated_at":"2026-11-02T14:32:57.033395Z"}],"euvd":[{"id":"EUVD-2021-13711","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2021-02-14T03:43:49Z","modified":"2024-08-03T20:33:41Z","updated_at":"2026-11-03T03:24:50.84326Z"}],"ghsa":[{"id":"GHSA-qc5g-54hm-vfmc","title":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the...","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2022-05-24T17:42:08Z","modified":"2024-04-04T03:04:39Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:56:13.24073Z"}],"nvd":[{"id":"CVE-2021-26929","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2021-02-14T04:15:12.777Z","modified":"2026-06-17T03:44:01.673Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:06:50.031227Z"}],"osv":[{"id":"CVE-2021-26929","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2021-02-14T04:15:12.777Z","modified":"2026-10-24T10:50:11.808093686Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:18.778776Z"},{"id":"DEBIAN-CVE-2021-26929","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2021-02-14T04:15:12.777Z","modified":"2026-10-23T18:03:25.650246972Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:34.637046Z"},{"id":"UBUNTU-CVE-2021-26929","description":"An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \\x00\\x00\\x00 and \\x01\\x01\\x01 interferes with XSS defenses.","status":"published","published":"2021-02-14T04:15:00Z","modified":"2025-10-24T04:50:10Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:26.779273Z"},{"id":"DLA-2564-1","title":"php-horde-text-filter - security update","status":"published","published":"2021-02-18T00:00:00Z","modified":"2026-03-09T01:21:28.319178Z","updated_at":"2026-11-02T15:46:10.712745Z"}]}}