{"id":"CVE-2025-53480","aliases":["EUVD-2025-20516","GHSA-66x3-m6h7-8jgc"],"status":"published","title":"CheckUser: Reflected Cross-Site Scripting (XSS) in Special:Investigate (Account information tab) via unsanitized i18n messages","description":"The CheckUser extension’s Special:Investigate page has a vulnerability in the Account information tab, where specific internationalized messages are rendered without proper escaping. Attackers can exploit this by appending ?uselang=x-xss to the URL, causing reflected XSS when the UI renders affected message keys.\n\n\n\n\nThis issue affects Mediawiki - CheckUser extension: from 1.39.X before 1.39.13, from 1.42.X before 1.42.7, from 1.43.X before 1.43.2.","severity":{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-10","score":0.00198,"percentile":0.09702,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2025-07-08T14:58:37Z","modified":"2026-06-17T09:38:17Z","products":[{"vendor":"the wikimedia foundation","product":"mediawiki - checkuser extension"},{"vendor":"wikimedia foundation","product":"mediawiki - checkuser extension"}],"references":[{"url":"https://phabricator.wikimedia.org/T394700"},{"url":"https://gerrit.wikimedia.org/r/q/I777fc55fef15c3b00df0db268af2b64cb2d6e381"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-53480"},{"url":"https://github.com/advisories/GHSA-66x3-m6h7-8jgc"}],"sources":{"cve":[{"id":"CVE-2025-53480","title":"CheckUser: Reflected Cross-Site Scripting (XSS) in Special:Investigate (Account information tab) via unsanitized i18n messages","description":"The CheckUser extension’s Special:Investigate page has a vulnerability in the Account information tab, where specific internationalized messages are rendered without proper escaping. Attackers can exploit this by appending ?uselang=x-xss to the URL, causing reflected XSS when the UI renders affected message keys.\n\n\n\n\nThis issue affects Mediawiki - CheckUser extension: from 1.39.X before 1.39.13, from 1.42.X before 1.42.7, from 1.43.X before 1.43.2.","status":"published","published":"2025-07-08T14:58:37.544Z","modified":"2025-07-08T20:44:54.968Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"adp"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:32:49.180768Z"}],"euvd":[{"id":"EUVD-2025-20516","description":"The CheckUser extension’s Special:Investigate page has a vulnerability in the Account information tab, where specific internationalized messages are rendered without proper escaping. Attackers can exploit this by appending ?uselang=x-xss to the URL, causing reflected XSS when the UI renders affected message keys.\n\n\n\n\nThis issue affects Mediawiki - CheckUser extension: from 1.39.X before 1.39.13, from 1.42.X before 1.42.7, from 1.43.X before 1.43.2.","status":"published","published":"2025-07-08T14:58:37Z","modified":"2025-07-08T20:44:54Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T20:32:10.524333Z"}],"ghsa":[{"id":"GHSA-66x3-m6h7-8jgc","title":"The CheckUser extension’s Special:Investigate page has a vulnerability in the Account information...","description":"The CheckUser extension’s Special:Investigate page has a vulnerability in the Account information tab, where specific internationalized messages are rendered without proper escaping. Attackers can exploit this by appending ?uselang=x-xss to the URL, causing reflected XSS when the UI renders affected message keys.\n\n\n\n\nThis issue affects Mediawiki - CheckUser extension: from 1.39.X before 1.39.13, from 1.42.X before 1.42.7, from 1.43.X before 1.43.2.","status":"published","published":"2025-07-08T15:32:03Z","modified":"2025-07-08T21:30:27Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:02:57.612558Z"}],"nvd":[{"id":"CVE-2025-53480","description":"The CheckUser extension’s Special:Investigate page has a vulnerability in the Account information tab, where specific internationalized messages are rendered without proper escaping. Attackers can exploit this by appending ?uselang=x-xss to the URL, causing reflected XSS when the UI renders affected message keys.\n\n\n\n\nThis issue affects Mediawiki - CheckUser extension: from 1.39.X before 1.39.13, from 1.42.X before 1.42.7, from 1.43.X before 1.43.2.","status":"published","published":"2025-07-08T15:15:29.72Z","modified":"2026-06-17T09:38:17.197Z","cvss":[{"version":"3.1","score":5.4,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:11:16.997062Z"}]}}