{"id":"CVE-2021-25218","aliases":["ALPINE-CVE-2021-25218","BELL-CVE-2021-25218","EUVD-2021-12129","GHSA-cc8x-chx9-c63q","openSUSE-SU-2024:10650-1"],"status":"published","title":"A too-strict assertion check could be triggered when responses in BIND 9.16.19 and 9.17.16 require UDP fragmentation if RRL is in use","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","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":"cna","from":"cve"},"epss":{"day":"2026-11-07","score":0.03658,"percentile":0.89691,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-617"],"published":"2021-08-18T18:20:11Z","modified":"2026-10-24T10:30:56Z","fixes":[{"ecosystem":"Alpine:v3.11","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.12","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.13","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.14","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.15","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.16","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.17","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.18","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.19","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.20","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.21","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.22","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.23","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"bind","fixed_in":["9.16.20-r0"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.11","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.12","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.13","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.14","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.15","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.16","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.17","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.18","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.19","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.20","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.21","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.22","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.23","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-r0"}]}]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"bind","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.16.20-1.4"}]}],"bundled":32}],"products":[{"vendor":"fedoraproject","product":"fedora"},{"vendor":"isc","product":"bind"},{"vendor":"isc","product":"bind9"}],"references":[{"url":"https://kb.isc.org/v1/docs/cve-2021-25218","tags":["x_refsource_CONFIRM","x_transferred","Exploit","Vendor Advisory","evidence"]},{"url":"http://www.openwall.com/lists/oss-security/2021/08/18/3","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Patch","Third Party Advisory","fix"]},{"url":"http://www.openwall.com/lists/oss-security/2021/08/20/2","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Patch","Third Party Advisory","fix"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZPJCLGSR4BTGFLBLGIE5TEQP2SNJKGVL/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://security.netapp.com/advisory/ntap-20210909-0002/","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-25218"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZPJCLGSR4BTGFLBLGIE5TEQP2SNJKGVL/"},{"url":"https://github.com/advisories/GHSA-cc8x-chx9-c63q"},{"url":"https://security.alpinelinux.org/vuln/CVE-2021-25218","tags":["advisory"]},{"url":"https://docs.bell-sw.com/security/cves/CVE-2021-25218","tags":["advisory"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2006-4339","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2007-2925","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2007-2926","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2015-8461","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2016-2775","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2016-9131","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2016-9778","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2017-3135","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2017-3141","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2017-3142","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2017-3145","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-5737","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-5743","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2018-5745","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-6465","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-6471","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-6476","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-6477","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8616","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8617","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8618","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8619","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8620","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8621","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8622","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8623","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8624","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-8625","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-25214","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-25215","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-25216","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-25218","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2021-25218","title":"A too-strict assertion check could be triggered when responses in BIND 9.16.19 and 9.17.16 require UDP fragmentation if RRL is in use","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","status":"published","published":"2021-08-18T18:20:11.962Z","modified":"2024-09-17T03:07:43.591Z","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":"cna"}],"updated_at":"2026-11-02T14:32:59.430294Z"}],"euvd":[{"id":"EUVD-2021-12129","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","status":"published","published":"2021-08-18T18:20:11Z","modified":"2024-09-17T03:07:43Z","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":"2026-11-03T00:28:34.673232Z"}],"ghsa":[{"id":"GHSA-cc8x-chx9-c63q","title":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a...","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","status":"published","published":"2022-05-24T19:11:29Z","modified":"2023-01-30T05:01:34Z","cwes":["CWE-617"],"updated_at":"2026-11-02T14:46:26.483285Z"}],"nvd":[{"id":"CVE-2021-25218","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","status":"published","published":"2021-08-18T19:15:07.333Z","modified":"2026-06-17T03:41:39.827Z","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":"secondary"},{"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-617"],"updated_at":"2026-11-02T14:06:57.318236Z"}],"osv":[{"id":"ALPINE-CVE-2021-25218","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","status":"published","published":"2021-08-18T19:15:07.333Z","modified":"2026-10-23T17:17:56.16101024Z","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":"2026-11-02T15:27:48.646074Z"},{"id":"BELL-CVE-2021-25218","title":"CVE-2021-25218 does not affect BellSoft software","status":"withdrawn","published":"2023-08-31T12:14:51.867086Z","modified":"2026-01-26T09:50:03.356856Z","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":"2026-11-02T15:28:15.925958Z"},{"id":"CVE-2021-25218","description":"In BIND 9.16.19, 9.17.16. Also, version 9.16.19-S1 of BIND Supported Preview Edition When a vulnerable version of named receives a query under the circumstances described above, the named process will terminate due to a failed assertion check. The vulnerability affects only BIND 9 releases 9.16.19, 9.17.16, and release 9.16.19-S1 of the BIND Supported Preview Edition.","status":"published","published":"2021-08-18T19:15:07.333Z","modified":"2026-10-24T10:30:56.524370189Z","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":"2026-11-02T15:44:18.778776Z"},{"id":"openSUSE-SU-2024:10650-1","title":"bind-9.16.20-1.4 on GA media","description":"These are all security issues fixed in the bind-9.16.20-1.4 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-06-15T00:00:00Z","modified":"2026-02-04T02:52:09.525836Z","updated_at":"2026-11-02T16:58:34.487567Z"}]}}