{"id":"CVE-2021-20247","aliases":["ALPINE-CVE-2021-20247","DEBIAN-CVE-2021-20247","DLA-3066-1","EUVD-2021-7686","GHSA-5cp5-w68m-9w38","UBUNTU-CVE-2021-20247","openSUSE-SU-2021:0516-1","openSUSE-SU-2021:0533-1","openSUSE-SU-2024:10866-1"],"status":"published","title":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by...","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","severity":{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.0188,"percentile":0.79725,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20","CWE-22"],"published":"2021-02-23T18:45:29Z","modified":"2026-11-03T06:32:26Z","fixes":[{"ecosystem":"Alpine:v3.13","package":"isync","fixed_in":["1.3.5-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.14","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.15","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.16","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.17","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.18","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.19","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.20","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.21","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.22","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.23","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"isync","fixed_in":["1.4.1-r0"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"isync","fixed_in":["1.3.0-2.1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"isync","fixed_in":["1.3.0-2.1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"isync","fixed_in":["1.3.0-2.1"],"sources":["osv"]},{"ecosystem":"openSUSE:Leap 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SP2","package":"isync","fixed_in":["1.3.5-bp152.4.3.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.13","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.5-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.14","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.15","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.16","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.17","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.18","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.19","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.20","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.21","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.22","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.23","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.1-r0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.0-2.1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.0-2.1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.0-2.1"}]}]},{"source":"osv","ecosystem":"Debian:9","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.1-2+deb9u1"}]}],"versions":["1.2.1-2"],"bundled":3},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.1.2-1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.2.1-2","1.3.0-1","1.3.0-1build1","1.3.0-1ubuntu0.18.04.0"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-2"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-2.2","1.4.3-1","1.4.4-1","1.4.4-3","1.4.4-3ubuntu0.22.04.1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.4-5","1.4.4-5build2","1.4.4-5build3"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.4-5build3","1.5.1-1ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.1-1ubuntu2","1.5.1-1ubuntu4"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.1-1ubuntu1","1.5.1-1ubuntu2"]},{"source":"osv","ecosystem":"openSUSE:Leap 15.2","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.5-lp152.4.3.1"}]}]},{"source":"osv","ecosystem":"SUSE:Package Hub 15 SP2","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.5-bp152.4.3.1"}]}]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"isync","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.3-1.2"}]}],"bundled":2}],"products":[{"vendor":"debian","product":"debian_linux"},{"vendor":"fedoraproject","product":"extra_packages_for_enterprise_linux"},{"vendor":"fedoraproject","product":"fedora"},{"vendor":"mbsync_project","product":"mbsync"}],"references":[{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1928963","tags":["x_refsource_MISC","x_transferred","Issue Tracking","Third Party Advisory","report"]},{"url":"https://www.openwall.com/lists/oss-security/2021/02/22/1","tags":["x_refsource_MISC","x_transferred","Exploit","Mailing List","Third Party Advisory","evidence","report"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CAXQLCK35QGRCRENRTGKJO4VVZGUXUJJ/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GVDEBZQJMWDW5JFK4NTHH6DAFNAZTESW/","tags":["vendor-advisory","x_refsource_FEDORA","x_transferred","web"]},{"url":"https://lists.debian.org/debian-lts-announce/2022/07/msg00001.html","tags":["mailing-list","x_refsource_MLIST","x_transferred","Mailing List","Third Party Advisory","advisory"]},{"url":"https://security.gentoo.org/glsa/202208-15","tags":["vendor-advisory","x_refsource_GENTOO","x_transferred","Third Party Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-20247"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/CAXQLCK35QGRCRENRTGKJO4VVZGUXUJJ/"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GVDEBZQJMWDW5JFK4NTHH6DAFNAZTESW/"},{"url":"https://github.com/advisories/GHSA-5cp5-w68m-9w38"},{"url":"https://security.alpinelinux.org/vuln/CVE-2021-20247","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-20247","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-20247","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-20247","tags":["report"]},{"url":"https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/thread/JHTHLJJZ7MOC6CJIECK5ALGTVO4U32PO/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1182488","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2021-20247","tags":["web"]},{"url":"https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/thread/CUG4AQOC7O5ZIO7I7EZZLO7RH35I3UPI/","tags":["advisory"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2021-3578","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2021-20247","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T18:45:29Z","modified":"2024-08-03T17:37:23.202Z","cwes":["CWE-20"],"updated_at":"2026-11-02T14:32:55.19484Z"}],"euvd":[{"id":"EUVD-2021-7686","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T18:45:29Z","modified":"2024-08-03T17:37:23Z","updated_at":"2026-11-03T03:25:09.355483Z"}],"ghsa":[{"id":"GHSA-5cp5-w68m-9w38","title":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by...","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2022-05-24T17:42:54Z","modified":"2023-02-01T05:02:16Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-20","CWE-22"],"updated_at":"2026-11-02T14:49:52.829666Z"}],"nvd":[{"id":"CVE-2021-20247","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T19:15:13.51Z","modified":"2026-06-17T03:33:32.533Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":5.8,"vector":"AV:N/AC:M/Au:N/C:P/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-20","CWE-22"],"updated_at":"2026-11-02T14:06:50.031227Z"}],"osv":[{"id":"ALPINE-CVE-2021-20247","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T19:15:13.51Z","modified":"2026-11-03T06:32:26.888366436Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T07:17:57.723967Z"},{"id":"CVE-2021-20247","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T19:15:13.51Z","modified":"2026-03-15T22:38:47.783089Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:18.004149Z"},{"id":"DEBIAN-CVE-2021-20247","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T19:15:13.51Z","modified":"2026-10-23T18:03:10.497507326Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:45:34.637046Z"},{"id":"UBUNTU-CVE-2021-20247","description":"A flaw was found in mbsync before v1.3.5 and v1.4.1. Validations of the mailbox names returned by IMAP LIST/LSUB do not occur allowing a malicious or compromised server to use specially crafted mailbox names containing '..' path components to access data outside the designated mailbox on the opposite end of the synchronization channel. The highest threat from this vulnerability is to data confidentiality and integrity.","status":"published","published":"2021-02-23T19:15:00Z","modified":"2026-10-17T12:56:19.38826662Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:54:25.728622Z"},{"id":"DLA-3066-1","title":"isync - security update","status":"published","published":"2022-07-01T00:00:00Z","modified":"2026-03-09T01:18:03.876911Z","updated_at":"2026-11-02T15:46:11.189256Z"},{"id":"openSUSE-SU-2021:0516-1","title":"Security update for isync","description":"This update for isync fixes the following issues:\n\n- isync was updated to version 1.3.5 \n- CVE-2021-20247: reject funny mailbox names from IMAP LIST/LSUB (boo#1182488)\n","status":"published","published":"2021-04-07T13:21:23Z","modified":"2026-02-04T03:26:57.660835Z","updated_at":"2026-11-02T16:58:31.879684Z"},{"id":"openSUSE-SU-2021:0533-1","title":"Security update for isync","description":"This update for isync fixes the following issues:\n\n- isync was updated to version 1.3.5 \n- CVE-2021-20247: reject funny mailbox names from IMAP LIST/LSUB (boo#1182488)\n\nThis update was imported from the openSUSE:Leap:15.2:Update update project.","status":"published","published":"2021-04-10T18:05:13Z","modified":"2026-02-04T02:47:11.185133Z","updated_at":"2026-11-02T16:58:31.879684Z"},{"id":"openSUSE-SU-2024:10866-1","title":"isync-1.4.3-1.2 on GA media","description":"These are all security issues fixed in the isync-1.4.3-1.2 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-06-15T00:00:00Z","modified":"2026-02-04T03:53:15.747275Z","updated_at":"2026-11-02T16:58:34.894275Z"}]}}