{"id":"CVE-2021-28994","aliases":["EUVD-2021-15641","GHSA-796m-wc5q-p6qj","UBUNTU-CVE-2021-28994"],"status":"published","title":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10...","description":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.02049,"percentile":0.8139,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-400","CWE-770"],"published":"2021-03-31T22:11:56Z","modified":"2026-06-17T03:47:07Z","affected":[{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"kopanocore","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.1.0-3ubuntu5","8.1.0-3ubuntu6","8.3.4-4ubuntu4","8.5.2-1ubuntu1","8.5.5-0ubuntu1","8.5.5-0ubuntu1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"kopanocore","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.7.0-3build2","8.7.0-5ubuntu5","8.7.0-5ubuntu6","8.7.0-6ubuntu1","8.7.0-6ubuntu2","8.7.0-6ubuntu3","8.7.0-7ubuntu1","8.7.0-7ubuntu1.1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"kopanocore","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.7.0-7.1ubuntu4","8.7.0-7.1ubuntu6","8.7.0-7.1ubuntu7","8.7.0-7.1ubuntu8","8.7.0-7.1ubuntu10","8.7.0-7.1ubuntu10.1"]}],"products":[{"vendor":"kopano","product":"groupware_core"},{"vendor":"zarafa","product":"zarafa"}],"references":[{"url":"https://www.openwall.com/lists/oss-security/2021/03/19/6","tags":["x_refsource_MISC","x_transferred","Exploit","Mailing List","Third Party Advisory","report"]},{"url":"http://www.openwall.com/lists/oss-security/2021/04/01/1","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2021/04/25/1","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-28994"},{"url":"https://github.com/advisories/GHSA-796m-wc5q-p6qj"},{"url":"https://ubuntu.com/security/CVE-2021-28994","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-28994","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-28994","description":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.","status":"published","published":"2021-03-31T22:11:56Z","modified":"2024-08-03T21:55:12.276Z","updated_at":"2026-11-02T14:33:08.811269Z"}],"euvd":[{"id":"EUVD-2021-15641","description":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.","status":"published","published":"2021-03-31T22:11:56Z","modified":"2024-08-03T21:55:12Z","updated_at":"2026-11-03T03:24:45.541615Z"}],"ghsa":[{"id":"GHSA-796m-wc5q-p6qj","title":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10...","description":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.","status":"published","published":"2022-05-24T17:46:05Z","modified":"2023-01-27T05:02:44Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:42:05.930236Z"}],"nvd":[{"id":"CVE-2021-28994","description":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.","status":"published","published":"2021-03-31T23:15:11.767Z","modified":"2026-06-17T03:47:07.63Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:06:51.197859Z"}],"osv":[{"id":"UBUNTU-CVE-2021-28994","description":"kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.","status":"published","published":"2021-03-31T23:15:00Z","modified":"2026-04-22T12:51:17.982307Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:26.779273Z"}]}}