{"schemaVersion":3,"id":"CVE-2020-35479","aliases":["UBUNTU-CVE-2020-35479","DEBIAN-CVE-2020-35479"],"status":"published","duplicateOf":null,"title":null,"description":"MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php. Language::translateBlockExpiry itself does not escape in all code paths. For example, the return of Language::userTimeAndDate is is always unsafe for HTML in a month value. This affects MediaWiki 1.12.0 and later.","dates":{"published":"2020-12-18T07:42:25.000Z","modified":"2024-08-04T17:02:08.034Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":6.1,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":6.1,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","exploitability":7.2,"impact":4.5,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Debian","score":6.1,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","exploitability":7.2,"impact":4.5,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":6.1,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":4.3,"severity":"medium","vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.01486,"percentile":0.73824,"severity":"low","asOf":"2026-10-22T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-22T00:00:00.000Z","baselineScore":0.01486},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-22T00:00:00.000Z","score":0.01486,"percentile":0.73824}],"last30":[{"date":"2026-09-22T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.01486,"percentile":null},{"date":"2026-10-22T00:00:00.000Z","score":0.01486,"percentile":0.73824}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[{"id":"REF_66B8AAEF609FB857","name":"Exploit Reference (phabricator.wikimedia.org)","source":"reference","url":"https://phabricator.wikimedia.org/T268938","maturity":"unknown","reliabilityScore":0.2,"verified":false,"type":null,"platforms":[],"requiresAuth":null,"exploitdb":null,"metasploit":null}],"exploitCount":1,"weaknesses":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","description":"The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.","type":"weakness","status":"Stable","abstraction":"Base","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/79.html"}],"affected":[{"vendor":"debian","product":"mediawiki","name":"mediawiki","label":"mediawiki","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/mediawiki","purlType":"deb","versions":[{"text":"< 1:1.35.1-1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1:1.35.1-1","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"mediawiki","name":"mediawiki","label":"mediawiki","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/mediawiki","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"debian","product":"debian_linux","name":"debian linux","label":"debian_linux","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"9.0","noFixRecorded":false,"fixedIn":null},{"text":"10.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"9.0 | 10.0","eol":{"isEol":true,"eolDate":"2022-07-01T00:00:00.000Z","matchMethod":"cpe","cycle":{"name":"9","label":"9 (Stretch)","eolFrom":"2022-07-01T00:00:00.000Z","isLts":false,"isMaintained":true,"latestVersion":"9.13"},"product":{"name":"debian","label":"Debian","category":"os"}},"hubHref":"/vendor/debian/debian_linux"},{"vendor":"fedoraproject","product":"fedora","name":"fedora","label":"fedora","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"33","noFixRecorded":false,"fixedIn":null}],"versionsText":"33","eol":{"isEol":true,"eolDate":"2021-11-30T00:00:00.000Z","matchMethod":"cpe","cycle":{"name":"33","label":"33","eolFrom":"2021-11-30T00:00:00.000Z","isLts":false,"isMaintained":false,"latestVersion":null},"product":{"name":"fedora","label":"Fedora Linux","category":"os"}},"hubHref":"/vendor/fedoraproject/fedora"},{"vendor":"mediawiki","product":"mediawiki","name":"mediawiki","label":"mediawiki","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 1.12.0, < 1.35.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 1.12.0, < 1.35.1","eol":{"isEol":null,"eolDate":null,"matchMethod":"cpe","cycle":null,"product":{"name":"mediawiki","label":"MediaWiki","category":"server-app"}},"hubHref":"/vendor/mediawiki/mediawiki"}],"affectedCount":5,"eol":{"hasEol":true,"count":2},"references":[{"url":"https://phabricator.wikimedia.org/T268938","label":"phabricator.wikimedia.org/T268938","hostname":"phabricator.wikimedia.org","tags":["X Refsource MISC","REPORT","Exploit","Vendor Advisory"]},{"url":"https://lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.html","label":"lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.html","hostname":"lists.wikimedia.org","tags":["X Refsource MISC","REPORT","Mailing List","Release Notes","Vendor Advisory"]},{"url":"https://www.debian.org/security/2020/dsa-4816","label":"www.debian.org/security/2020/dsa-4816","hostname":"www.debian.org","tags":["Vendor Advisory","X Refsource DEBIAN","Third Party Advisory"]},{"url":"https://lists.debian.org/debian-lts-announce/2020/12/msg00034.html","label":"lists.debian.org/debian-lts-announce/2020/12/msg00034.html","hostname":"lists.debian.org","tags":["Mailing List","X Refsource MLIST","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC/","label":"lists.fedoraproject.org/archives/…","hostname":"lists.fedoraproject.org","tags":["Vendor Advisory","X Refsource FEDORA"]},{"url":"https://ubuntu.com/security/CVE-2020-35479","label":"ubuntu.com/security/CVE-2020-35479","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://lists.wikimedia.org/pipermail/wikitech-l/2020-December/094126.html","label":"lists.wikimedia.org/pipermail/wikitech-l/2020-December/094126.html","hostname":"lists.wikimedia.org","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-35479","label":"www.cve.org/CVERecord?id=CVE-2020-35479","hostname":"www.cve.org","tags":["REPORT"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2020-35479","label":"security-tracker.debian.org/tracker/CVE-2020-35479","hostname":"security-tracker.debian.org","tags":["Advisory"]}],"lineage":{"upstream":[],"downstream":["DLA-2504-1","DSA-4816-1","MGASA-2021-0086"],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2020-12-18T07:42:25.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-08-04T17:02:08.034Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":35,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-22T17:56:48.017Z","stale":false,"partial":false}}