{"id":"CVE-2026-39838","state":"PUBLISHED","title":"ProofreadPage improperly sanitizes multiline styles using Sanitizer::checkCSS","description":"Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation MediaWiki - ProofreadPage Extension allows XSS Targeting Non-Script Elements.\nThe issue has been remediated on the `master` branch, and in the release branches for MediaWiki versions 1.43, 1.44, and 1.45.","publishedAt":"2026-04-07T19:17:51.638Z","updatedAt":"2026-04-08T18:48:41.035Z","severity":{"score":6.9,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N","source":"wikimedia-foundation"},"assigner":"wikimedia-foundation","products":["Wikimedia Foundation MediaWiki - ProofreadPage Extension"],"affected":[{"vendor":"Wikimedia Foundation","product":"MediaWiki - ProofreadPage Extension","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"1.43","versionType":"custom"},{"version":"1.43","status":"unaffected"},{"version":"1.44","status":"unaffected"},{"version":"1.45","status":"unaffected"}]}],"references":["https://phabricator.wikimedia.org/T406088","https://gerrit.wikimedia.org/r/q/Idd51e18479b32b7176b43ff74ca1c49d6bdd0628"],"weaknesses":["CWE-79"],"ingestedAt":"2026-10-29T20:11:50.837Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/39xxx/CVE-2026-39838.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-39838","state":"PUBLISHED","datePublished":"2026-04-07T19:17:51.638Z","dateUpdated":"2026-04-08T18:48:41.035Z","assignerShortName":"wikimedia-foundation","assignerOrgId":"c4f26cc8-17ff-4c99-b5e2-38fc1793eacc","dateReserved":"2026-04-07T18:21:12.573Z"},"containers":{"cna":{"title":"ProofreadPage improperly sanitizes multiline styles using Sanitizer::checkCSS","descriptions":[{"lang":"en","value":"Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation MediaWiki - ProofreadPage Extension allows XSS Targeting Non-Script Elements.\nThe issue has been remediated on the `master` branch, and in the release branches for MediaWiki versions 1.43, 1.44, and 1.45."}],"affected":[{"vendor":"Wikimedia Foundation","product":"MediaWiki - ProofreadPage Extension","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"1.43","versionType":"custom"},{"version":"1.43","status":"unaffected"},{"version":"1.44","status":"unaffected"},{"version":"1.45","status":"unaffected"}]}],"references":[{"url":"https://phabricator.wikimedia.org/T406088"},{"url":"https://gerrit.wikimedia.org/r/q/Idd51e18479b32b7176b43ff74ca1c49d6bdd0628"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","subConfidentialityImpact":"LOW","vulnIntegrityImpact":"LOW","subIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"MEDIUM","baseScore":6.9,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-79","lang":"en","description":"CWE-79 Improper neutralization of input during web page generation ('cross-site scripting')","type":"CWE"}]}],"providerMetadata":{"shortName":"wikimedia-foundation","orgId":"c4f26cc8-17ff-4c99-b5e2-38fc1793eacc","dateUpdated":"2026-04-08T18:48:41.035Z"},"impacts":[{"capecId":"CAPEC-18","descriptions":[{"lang":"en","value":"CAPEC-18 XSS Targeting Non-Script Elements"}]}],"credits":[{"lang":"en","value":"SomeRandomDeveloper","type":"finder"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.1"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-39838","role":"CISA Coordinator","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-04-07T20:33:20.274715Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-07T20:42:43.371Z"}}]}}}