{"id":"CVE-2021-34434","aliases":["BELL-CVE-2021-34434","DEBIAN-CVE-2021-34434","DSA-5511-1","EUVD-2021-21090","GHSA-cj6r-mprf-8cq9","MGASA-2021-0445","UBUNTU-CVE-2021-34434","USN-6492-1","openSUSE-SU-2024:11575-1"],"status":"published","title":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the...","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.0133,"percentile":0.7147,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-285","CWE-863"],"published":"2021-08-30T00:00:00Z","modified":"2026-10-24T10:30:44Z","fixes":[{"ecosystem":"Debian:12","package":"mosquitto","fixed_in":["2.0.11-1.2+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"mosquitto","fixed_in":["2.0.15-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"mosquitto","fixed_in":["2.0.15-1"],"sources":["osv"]},{"ecosystem":"Mageia:8","package":"mosquitto","fixed_in":["2.0.12-1.mga8"],"sources":["osv"]},{"ecosystem":"Ubuntu:22.04:LTS","package":"mosquitto","fixed_in":["2.0.11-1ubuntu1.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.11-1.2+deb12u1"}]}],"versions":["2.0.11-1.2"]},{"source":"osv","ecosystem":"Debian:13","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.15-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.15-1"}]}]},{"source":"osv","ecosystem":"Debian:11","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.11-1+deb11u1"}]}],"versions":["2.0.11-1"],"bundled":4},{"source":"osv","ecosystem":"Debian:12","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.11-1.2+deb12u1"}]}],"versions":["2.0.11-1.2"],"bundled":4},{"source":"osv","ecosystem":"Mageia:8","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.12-1.mga8"}]}]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.11-1ubuntu1.1"}]}],"versions":["2.0.11-1","2.0.11-1build1","2.0.11-1ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.9-1ubuntu0.1~esm1"}]}],"versions":["1.6.6-1","1.6.7-1","1.6.8-1","1.6.8-2","1.6.9-1~build1","1.6.9-1"],"bundled":6},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"mosquitto","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.11-1ubuntu1.1"}]}],"versions":["2.0.11-1","2.0.11-1build1","2.0.11-1ubuntu1"],"bundled":6}],"products":[{"vendor":"eclipse","product":"mosquitto"},{"vendor":"fedoraproject","product":"fedora"},{"vendor":"the eclipse foundation","product":"eclipse mosquitto"}],"references":[{"url":"https://bugs.eclipse.org/bugs/show_bug.cgi?id=575324","tags":["x_transferred","Exploit","Issue Tracking","Vendor Advisory","report"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K4WWGVF5BUFPYPCFUPPP4KRIYI5OTJN2/","tags":["vendor-advisory","x_transferred","web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RLUUM52Y6AEICPXPSRRXC6OBY4H5XKW7/","tags":["vendor-advisory","x_transferred","web"]},{"url":"https://www.debian.org/security/2023/dsa-5511","tags":["vendor-advisory","x_transferred","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-34434"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/K4WWGVF5BUFPYPCFUPPP4KRIYI5OTJN2/"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RLUUM52Y6AEICPXPSRRXC6OBY4H5XKW7/"},{"url":"https://github.com/advisories/GHSA-cj6r-mprf-8cq9"},{"url":"https://docs.bell-sw.com/security/cves/CVE-2021-34434","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-34434","tags":["advisory"]},{"url":"https://advisories.mageia.org/MGASA-2021-0445.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=29454","tags":["report"]},{"url":"https://mosquitto.org/blog/2021/08/version-2-0-12-released/","tags":["web"]},{"url":"https://ubuntu.com/security/CVE-2021-34434","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-6492-1","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-34434","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-34431","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2021-41039","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2023-0809","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2023-3592","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2023-28366","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2020-13849","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-34434","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2021-34434","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2021-08-30T00:00:00Z","modified":"2024-08-04T00:12:50.159Z","cwes":["CWE-285"],"updated_at":"2026-11-02T14:33:11.244759Z"}],"euvd":[{"id":"EUVD-2021-21090","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2021-08-30T00:00:00Z","modified":"2024-08-04T00:12:50Z","updated_at":"2026-11-03T03:24:32.445199Z"}],"ghsa":[{"id":"GHSA-cj6r-mprf-8cq9","title":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the...","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2022-05-24T19:12:26Z","modified":"2023-10-02T12:30:23Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-285","CWE-863"],"updated_at":"2026-11-02T14:54:46.99514Z"}],"nvd":[{"id":"CVE-2021-34434","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2021-08-30T20:15:07.363Z","modified":"2026-06-17T03:55:51.627Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-285","CWE-863"],"updated_at":"2026-11-02T14:06:57.67549Z"}],"osv":[{"id":"BELL-CVE-2021-34434","title":"CVE-2021-34434 does not affect BellSoft software","status":"withdrawn","published":"2021-08-30T20:15:00Z","modified":"2026-01-26T09:49:29.449553Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:28:16.5265Z"},{"id":"CVE-2021-34434","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2021-08-30T20:15:07.363Z","modified":"2026-10-24T10:30:44.438072061Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:20.13324Z"},{"id":"DEBIAN-CVE-2021-34434","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2021-08-30T20:15:07.363Z","modified":"2026-10-23T18:04:50.631198374Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:35.233346Z"},{"id":"UBUNTU-CVE-2021-34434","description":"In Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security plugin, if the ability for a client to make subscriptions on a topic is revoked when a durable client is offline, then existing subscriptions for that client are not revoked.","status":"published","published":"2021-08-30T20:15:00Z","modified":"2026-04-22T12:55:55.83955Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:27.870979Z"},{"id":"DSA-5511-1","title":"mosquitto - security update","status":"published","published":"2023-10-01T00:00:00Z","modified":"2026-03-09T02:10:31.291593Z","updated_at":"2026-11-02T15:46:17.892347Z"},{"id":"MGASA-2021-0445","title":"Updated mosquitto packages fix security vulnerability","description":"Mosquitto is updated to 2.0.12 to fix security vulnerability:\n\nIn Eclipse Mosquitto versions 2.0 to 2.0.11, when using the dynamic security\nplugin, if the ability for a client to make subscriptions on a topic is\nrevoked when a durable client is offline, then existing subscriptions for\nthat client are not revoked (CVE-2021-34434).\n","status":"published","published":"2021-09-29T17:22:22Z","modified":"2026-04-16T04:41:04.407198741Z","updated_at":"2026-11-02T15:49:41.849028Z"},{"id":"openSUSE-SU-2024:11575-1","title":"libmosquitto1-2.0.12-1.1 on GA media","description":"These are all security issues fixed in the libmosquitto1-2.0.12-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-06-15T00:00:00Z","modified":"2026-02-04T03:25:40.712752Z","updated_at":"2026-11-02T16:58:35.195147Z"},{"id":"USN-6492-1","title":"mosquitto vulnerabilities","description":"Kathrin Kleinhammer discovered that Mosquitto incorrectly handled certain\ninputs. If a user or an automated system were provided with a specially crafted\ninput, a remote attacker could possibly use this issue to cause a denial of\nservice. This issue only affected Ubuntu 20.04 LTS. (CVE-2021-34431)\n\nZhanxiang Song discovered that Mosquitto incorrectly handled certain inputs. If\na user or an automated system were provided with a specially crafted input, a\nremote attacker could possibly use this issue to cause an authorisation bypass.\nThis issue only affected Ubuntu 22.04 LTS and Ubuntu 23.04. (CVE-2021-34434)\n\nZhanxiang Song, Bin Yuan, DeQing Zou, and Hai Jin discovered that Mosquitto\nincorrectly handled certain inputs. If a user or an automated system were\nprovided with a specially crafted input, a remote attacker could possibly use\nthis issue to cause a denial of service. This issue only affected Ubuntu 20.04\nLTS and Ubuntu 22.04 LTS. (CVE-2021-41039)\n\nZhengjie Du discovered that Mosquitto incorrectly handled certain inputs. If a\nuser or an automated system were provided with a specially crafted input file,\na remote attacker could possibly use this issue to cause a denial of service.\n(CVE-2023-0809)\n\nIt was discovered that Mosquitto incorrectly handled certain inputs. If a user\nor an automated system were provided with a specially crafted input, a remote\nattacker could possibly use this issue to cause a denial of service.\n(CVE-2023-3592)\n\nMischa Bachmann discovered that Mosquitto incorrectly handled certain inputs.\nIf a user or an automated system were provided with a specially crafted input,\na remote attacker could possibly use this issue to cause a denial of service.\nThis issue was only fixed in Ubuntu 22.04 LTS and Ubuntu 23.04.\n(CVE-2023-28366)\n","status":"published","published":"2023-11-21T15:23:51Z","modified":"2026-04-22T10:41:36.101799Z","updated_at":"2026-11-02T16:58:17.305935Z"}]}}