{"schemaVersion":3,"id":"CVE-2021-21608","aliases":["GHSA-wv63-gwr9-5c55","BIT-jenkins-2021-21608"],"status":"published","duplicateOf":null,"title":null,"description":"Jenkins 2.274 and earlier, LTS 2.263.1 and earlier does not escape button labels in the Jenkins UI, resulting in a cross-site scripting (XSS) vulnerability exploitable by attackers with the ability to control button labels.","dates":{"published":"2021-01-13T15:55:30.000Z","modified":"2024-08-03T18:16:23.633Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":5.4,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"OSV · Maven","score":5.4,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","exploitability":5.9,"impact":4.5,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":5.4,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/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":3.5,"severity":"low","vector":"AV:N/AC:M/Au:S/C:N/I:P/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.01041,"percentile":0.63513,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":0.012000000000000031,"baselineDate":"2026-09-20T00:00:00.000Z","baselineScore":0.01029},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.01041,"percentile":0.63513}],"last30":[{"date":"2026-09-20T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01029,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01041,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.01041,"percentile":0.63513}]},"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":[],"exploitCount":0,"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":"jenkins project","product":"jenkins","name":"Jenkins","label":"jenkins","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ unspecified, ≤ 2.274","noFixRecorded":false,"fixedIn":null},{"text":"≥ unspecified, ≤ LTS 2.263.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ unspecified, ≤ 2.274 | ≥ unspecified, ≤ LTS 2.263.1","eol":null,"hubHref":"/vendor/jenkins_project/jenkins"},{"vendor":"jenkins","product":"jenkins","name":"Jenkins","label":"jenkins","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≤ 2.263.1","noFixRecorded":false,"fixedIn":null},{"text":"≤ 2.274","noFixRecorded":false,"fixedIn":null}],"versionsText":"≤ 2.263.1 | ≤ 2.274","eol":{"isEol":null,"eolDate":null,"matchMethod":"cpe","cycle":null,"product":{"name":"jenkins","label":"Jenkins","category":"server-app"}},"hubHref":"/vendor/jenkins/jenkins"},{"vendor":"org.jenkins-ci.main","product":"jenkins-core","name":"org.jenkins-ci.main:jenkins-core","label":"jenkins-core","ecosystem":"Maven","cpePart":null,"purl":"pkg:maven/org.jenkins-ci.main/jenkins-core","purlType":"maven","versions":[{"text":"< 2.275","noFixRecorded":false,"fixedIn":null},{"text":"≥ 2.263.2, < 2.275","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 2.275 | ≥ 2.263.2, < 2.275","eol":null,"hubHref":null}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://www.jenkins.io/security/advisory/2021-01-13/#SECURITY-2035","label":"www.jenkins.io/security/advisory/2021-01-13/","hostname":"www.jenkins.io","tags":["X Refsource CONFIRM","WEB","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-21608","label":"nvd.nist.gov/vuln/detail/CVE-2021-21608","hostname":"nvd.nist.gov","tags":["Advisory"]},{"url":"https://github.com/jenkinsci/jenkins/commit/8c451b08886561a914ef0c30cbb9d40ea33a9bbe","label":"github.com/jenkinsci/jenkins/commit/8c451b08886561a914ef0c30cbb9d40ea33a9bbe","hostname":"github.com","tags":["WEB"]},{"url":"https://github.com/jenkinsci/jenkins","label":"github.com/jenkinsci/jenkins","hostname":"github.com","tags":["PACKAGE"]}],"lineage":{"upstream":[],"downstream":["RHSA-2021:0423","RHSA-2021:0429","RHSA-2021:0637","RHSA-2021:2437"],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2021-01-13T15:55:30.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-08-03T18:16:23.633Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":22,"level":"low","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T19:36:57.193Z","stale":false,"partial":false}}