{"id":"CVE-2021-44856","aliases":["BIT-mediawiki-2021-44856","DEBIAN-CVE-2021-44856","DLA-3117-1","DSA-5246-1","EUVD-2021-31659","GHSA-gmch-57w2-pj7q","MGASA-2021-0568","UBUNTU-CVE-2021-44856"],"status":"published","title":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37...","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.00525,"percentile":0.44874,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-754"],"published":"2021-12-19T12:26:08Z","modified":"2026-10-24T10:30:44Z","fixes":[{"ecosystem":"Bitnami","package":"mediawiki","fixed_in":["1.35.5","1.36.3","1.37.1"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"mediawiki","fixed_in":["1:1.35.5-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"mediawiki","fixed_in":["1:1.35.5-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"mediawiki","fixed_in":["1:1.35.5-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Bitnami","package":"mediawiki","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.35.5"},{"introduced":"1.36.0"},{"fixed":"1.36.3"},{"introduced":"1.37.0"},{"fixed":"1.37.1"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.35.5-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.35.5-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.35.5-1"}]}]},{"source":"osv","ecosystem":"Debian:10","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.31.16-1+deb10u3"}]}],"versions":["1:1.31.10-1~deb10u1","1:1.31.12-1~deb10u1","1:1.31.14-1~deb10u1","1:1.31.16-1+deb10u2","1:1.31.16-1~deb10u1","1:1.31.2-1","1:1.31.4-1","1:1.31.4-1~deb10u1","1:1.31.5-1","1:1.31.5-2","1:1.31.5-3","1:1.31.6-1","1:1.31.6-1~deb10u1","1:1.31.7-1","1:1.31.7-1~deb10u1","1:1.31.8-1"],"bundled":6},{"source":"osv","ecosystem":"Debian:11","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:1.35.8-1~deb11u1"}]}],"versions":["1:1.35.2-1","1:1.35.3-1","1:1.35.4-1","1:1.35.4-1+deb11u2","1:1.35.4-1~deb11u1","1:1.35.5-1","1:1.35.5-2","1:1.35.6-1","1:1.35.7-1"],"bundled":15},{"source":"osv","ecosystem":"Mageia:8","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.35.5-1.mga8"}]}],"bundled":6},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:1.27.3-1","1:1.27.4-1","1:1.27.4-2","1:1.27.4-3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"mediawiki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:1.31.2-1ubuntu1","1:1.31.5-1","1:1.31.5-1ubuntu1","1:1.31.5-2","1:1.31.5-3","1:1.31.5-3ubuntu1","1:1.31.6-1","1:1.31.7-1","1:1.31.7-1ubuntu0.1~esm1"]}],"products":[{"vendor":"mediawiki","product":"mediawiki"}],"references":[{"url":"https://phabricator.wikimedia.org/T271037","tags":["x_transferred","Issue Tracking","Patch","Vendor Advisory","web","fix","report"]},{"url":"https://security.gentoo.org/glsa/202305-24","tags":["x_transferred","web","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-44856","tags":["web"]},{"url":"https://github.com/advisories/GHSA-gmch-57w2-pj7q"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-44856","tags":["advisory"]},{"url":"https://advisories.mageia.org/MGASA-2021-0568.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=29772","tags":["report"]},{"url":"https://lists.wikimedia.org/hyperkitty/list/mediawiki-announce@lists.wikimedia.org/thread/QEN3EK4JXAVJMJ5GF3GYOAKNJPEKFQYA/","tags":["web"]},{"url":"https://ubuntu.com/security/CVE-2021-44856","tags":["report"]},{"url":"https://lists.wikimedia.org/hyperkitty/list/wikitech-l@lists.wikimedia.org/thread/QEN3EK4JXAVJMJ5GF3GYOAKNJPEKFQYA/","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-44856","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-44856","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T00:00:00Z","modified":"2025-04-14T15:49:47.008Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"adp"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T14:33:01.166399Z"}],"euvd":[{"id":"EUVD-2021-31659","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T00:00:00Z","modified":"2025-04-14T15:49:47Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T20:52:33.465211Z"}],"ghsa":[{"id":"GHSA-gmch-57w2-pj7q","title":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37...","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T06:30:22Z","modified":"2023-05-22T00:30:20Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T14:54:36.087743Z"}],"nvd":[{"id":"CVE-2021-44856","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T06:15:10.737Z","modified":"2026-06-17T04:12:53.907Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-754"],"updated_at":"2026-11-02T14:07:07.323379Z"}],"osv":[{"id":"CVE-2021-44856","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T06:15:10.737Z","modified":"2026-10-24T10:30:44.535468687Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:21.877444Z"},{"id":"DEBIAN-CVE-2021-44856","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T06:15:10.737Z","modified":"2026-10-23T18:04:00.638552677Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:35.799676Z"},{"id":"UBUNTU-CVE-2021-44856","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2022-12-26T06:15:00Z","modified":"2026-05-27T10:17:06.945923313Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:30.277322Z"},{"id":"BIT-mediawiki-2021-44856","description":"An issue was discovered in MediaWiki before 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1. A title blocked by AbuseFilter can be created via Special:ChangeContentModel due to the mishandling of the EditFilterMergedContent hook return value.","status":"published","published":"2024-03-06T11:09:34.183Z","modified":"2025-04-03T14:40:37.652Z","updated_at":"2026-11-02T15:28:33.072289Z"},{"id":"DLA-3117-1","title":"mediawiki - security update","status":"published","published":"2022-09-22T00:00:00Z","modified":"2026-03-09T01:22:59.339357Z","updated_at":"2026-11-02T15:46:11.189256Z"},{"id":"DSA-5246-1","title":"mediawiki - security update","status":"published","published":"2022-10-04T00:00:00Z","modified":"2026-03-09T02:10:52.19395Z","updated_at":"2026-11-02T15:46:17.543497Z"},{"id":"MGASA-2021-0568","title":"Updated mediawiki packages fix security vulnerabilities","description":"Updated mediawiki packages fix security vulnerabilities:\n\n== Security fixes ==\n* (T292763. CVE-2021-44854) REST API incorrectly publicly caches\n  autocomplete search results from private wikis.\n* (T271037, CVE-2021-44856) Title blocked in AbuseFilter can be created via\n  Special:ChangeContentModel.\n* (T297322, CVE-2021-44857) Unauthorized users can use action=mcrundo to\n  replace the content of arbitrary pages.\n* (T297322, CVE-2021-44858) Unauthorized users can view contents of private\n   wikis using various actions.\n* (T297574, CVE-2021-45038) Unauthorized users can access private wiki\n  contents using rollback action\n\n=== Extension security fixes ===\n* (T293589, CVE-2021-44855) Blind Stored XSS in VisualEditor media dialog.\n* (T294686) Special:Nuke doesn't actually delete pages.\n","status":"published","published":"2021-12-19T12:26:08Z","modified":"2026-04-16T04:41:07.079064181Z","updated_at":"2026-11-02T15:49:41.849028Z"}]}}