{"id":"CVE-2020-16127","aliases":["EUVD-2020-8093","GHSA-vg2p-x98m-7mxr","UBUNTU-CVE-2020-16127","USN-4616-1"],"status":"published","title":"accountsservice .pam_environment infinite loop","description":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, would perform unbounded read operations on user-controlled ~/.pam_environment files, allowing an infinite loop if /dev/zero is symlinked to this location.","severity":{"version":"3.1","score":2.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00414,"percentile":0.36166,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20","CWE-835"],"published":"2020-11-03T00:00:00Z","modified":"2026-06-17T02:57:45Z","fixes":[{"ecosystem":"Ubuntu:20.04:LTS","package":"accountsservice","fixed_in":["0.6.55-0ubuntu12~20.04.4"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"accountsservice","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.55-0ubuntu12~20.04.4"}]}],"versions":["0.6.55-0ubuntu10","0.6.55-0ubuntu11","0.6.55-0ubuntu12~20.04.1","0.6.55-0ubuntu12~20.04.2"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"accountsservice","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.40-2ubuntu11.6"}]}],"versions":["0.6.40-2ubuntu5","0.6.40-2ubuntu6","0.6.40-2ubuntu7","0.6.40-2ubuntu8","0.6.40-2ubuntu9","0.6.40-2ubuntu10","0.6.40-2ubuntu11","0.6.40-2ubuntu11.1","0.6.40-2ubuntu11.2","0.6.40-2ubuntu11.3"],"bundled":3},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"accountsservice","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.45-1ubuntu1.3"}]}],"versions":["0.6.42-0ubuntu3","0.6.42-0ubuntu4","0.6.45-1ubuntu1"],"bundled":3},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"accountsservice","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.55-0ubuntu12~20.04.4"}]}],"versions":["0.6.55-0ubuntu10","0.6.55-0ubuntu11","0.6.55-0ubuntu12~20.04.1","0.6.55-0ubuntu12~20.04.2"],"bundled":3}],"products":[{"vendor":"freedesktop","product":"accountsservice"},{"vendor":"ubuntu","product":"accountsservice"}],"references":[{"url":"https://securitylab.github.com/advisories/GHSL-2020-187-accountsservice-drop-privs-DOS","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-16127"},{"url":"https://github.com/advisories/GHSA-vg2p-x98m-7mxr"},{"url":"https://ubuntu.com/security/CVE-2020-16127","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-4616-1","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-16127","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-14036","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-16126","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2020-16127","title":"accountsservice .pam_environment infinite loop","description":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, would perform unbounded read operations on user-controlled ~/.pam_environment files, allowing an infinite loop if /dev/zero is symlinked to this location.","status":"published","published":"2020-11-11T04:10:15.512Z","modified":"2024-09-16T17:58:49.219Z","cvss":[{"version":"3.1","score":2.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L","level":"low","assessor":"cna"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:35:59.116379Z"}],"euvd":[{"id":"EUVD-2020-8093","description":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, would perform unbounded read operations on user-controlled ~/.pam_environment files, allowing an infinite loop if /dev/zero is symlinked to this location.","status":"published","published":"2020-11-11T04:10:15Z","modified":"2024-09-16T17:58:49Z","cvss":[{"version":"3.1","score":2.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-03T00:55:36.806318Z"}],"ghsa":[{"id":"GHSA-vg2p-x98m-7mxr","title":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among...","description":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, would perform unbounded read operations on user-controlled ~/.pam_environment files, allowing an infinite loop if /dev/zero is symlinked to this location.","status":"published","published":"2022-05-24T17:33:38Z","modified":"2023-01-29T05:04:39Z","cwes":["CWE-835"],"updated_at":"2026-11-02T14:45:36.557586Z"}],"nvd":[{"id":"CVE-2020-16127","description":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, would perform unbounded read operations on user-controlled ~/.pam_environment files, allowing an infinite loop if /dev/zero is symlinked to this location.","status":"published","published":"2020-11-11T04:15:12.177Z","modified":"2026-06-17T02:57:45.447Z","cvss":[{"version":"3.1","score":2.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L","level":"low","assessor":"secondary"},{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"2.0","score":2.1,"vector":"AV:L/AC:L/Au:N/C:N/I:N/A:P","level":"low","assessor":"primary"}],"cwes":["CWE-20","CWE-835"],"updated_at":"2026-11-02T14:06:24.137599Z"}],"osv":[{"id":"UBUNTU-CVE-2020-16127","description":"An Ubuntu-specific modification to AccountsService in versions before 0.6.55-0ubuntu13.2, among other earlier versions, would perform unbounded read operations on user-controlled ~/.pam_environment files, allowing an infinite loop if /dev/zero is symlinked to this location.","status":"published","published":"2020-11-03T00:00:00Z","modified":"2026-04-22T12:31:36.66506Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"},{"version":"3.1","score":2.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-02T15:54:23.344108Z"},{"id":"USN-4616-1","title":"accountsservice vulnerabilities","description":"Kevin Backhouse discovered that AccountsService incorrectly dropped\nprivileges. A local user could possibly use this issue to cause\nAccountsService to crash or hang, resulting in a denial of service.\n(CVE-2020-16126)\n\nKevin Backhouse discovered that AccountsService incorrectly handled reading\n.pam_environment files. A local user could possibly use this issue to cause\nAccountsService to crash or hang, resulting in a denial of service. This\nissue only affected Ubuntu 20.04 LTS and Ubuntu 20.10. (CVE-2020-16127)\n\nMatthias Gerstner discovered that AccountsService incorrectly handled\ncertain path checks. A local attacker could possibly use this issue to\nread arbitrary files. This issue only affected Ubuntu 16.04 LTS and Ubuntu\n18.04 LTS. (CVE-2018-14036)\n","status":"published","published":"2020-11-03T15:16:30Z","modified":"2026-04-22T10:09:30.186922Z","updated_at":"2026-11-02T16:58:15.159055Z"}]}}