Reflected XSS in Wikibase Special:SetLabel language validation

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-100380",
    "assignerOrgId": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
    "assignerShortName": "wikimedia-foundation",
    "dateUpdated": "2026-09-25T20:58:24.004Z",
    "dateReserved": "2026-09-25T19:28:11.982Z",
    "datePublished": "2026-09-25T20:58:24.004Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
        "shortName": "wikimedia-foundation",
        "dateUpdated": "2026-09-25T20:58:24.004Z"
      },
      "title": "Reflected XSS in Wikibase Special:SetLabel language validation",
      "descriptions": [
        {
          "lang": "en",
          "value": "Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki - Wikibase Extension allows Cross-Site Scripting (XSS).\n\nThis issue affects Mediawiki - Wikibase Extension: from * before 1.46.1, 1.45.5, 1.43.10.",
          "supportingMedia": [
            {
              "type": "text/html",
              "base64": false,
              "value": "Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation Mediawiki - Wikibase Extension allows Cross-Site Scripting (XSS).<p>This issue affects Mediawiki - Wikibase Extension: from * before 1.46.1, 1.45.5, 1.43.10.</p>"
            }
          ]
        }
      ],
      "affected": [
        {
          "vendor": "Wikimedia Foundation",
          "product": "Mediawiki - Wikibase Extension",
          "repo": "https://gerrit.wikimedia.org/g/mediawiki/extensions/Wikibase/+/refs/heads/master",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "*",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "1.46.1, 1.45.5, 1.43.10"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')",
              "cweId": "CWE-79",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://phabricator.wikimedia.org/T434549"
        },
        {
          "url": "https://gerrit.wikimedia.org/r/q/I7407f9748d72161ce25ad0ba2446869bb1776857"
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-63",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-63 Cross-Site Scripting (XSS)"
            }
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Marco Paciaroni (bombobombone)",
          "type": "finder"
        }
      ]
    }
  }
}