{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "cveMetadata": {
    "cveId": "CVE-2025-62698",
    "assignerOrgId": "00000000-0000-4000-9000-000000000000",
    "requesterUserId": "00000000-0000-4000-9000-000000000000",
    "serial": 1,
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "00000000-0000-4000-9000-000000000000"
      },
      "title": "Stored XSS through system messages in the MediaWiki ExternalGuidance extension",
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "cweId": "CWE-79",
              "description": "CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')",
              "type": "CWE"
            }
          ]
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-592",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-592 Stored XSS"
            }
          ]
        }
      ],
      "affected": [
        {
          "vendor": "MediaWiki",
          "product": "ExternalGuidance extension",
          "repo": "https://gerrit.wikimedia.org/g/mediawiki/extensions/ExternalGuidance",
          "programFiles": [
            "modules/mw.externalguidance/core.js"
          ],
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "c7c51ca611",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0",
              "lessThan": "22986d5fd1",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0",
              "lessThan": "c0a0d0e568",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "0",
              "lessThan": "3d6e2f673a",
              "versionType": "git"
            }
          ],
          "defaultStatus": "affected"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A stored cross-site scripting (XSS) vulnerability in the MediaWiki ExternalGuidance extension enabled users with the editinterface right, but without the editsitejs/editsitecss rights (notably, including the default sysop user-group), to execute arbitrary JavaScript in some end-users' web browsers, by overriding certain system messages which the ExternalGuidance extension inserted into the page as raw HTML.\n\nThe vulnerable system messages were:\n\n  *  externalguidance-machine-translation-heading\n  *  externalguidance-machine-translation-contribute\n\n\n\n\nThis issue affects all versions of the ExternalGuidance extension before Git commits c7c51ca611 (branch master), before 22986d5fd1 (branch REL1_44), before c0a0d0e568 (branch REL1_43), & before 3d6e2f673a (branch REL1_39).",
          "supportingMedia": [
            {
              "type": "text/html",
              "base64": false,
              "value": "<p>A stored cross-site scripting (XSS) vulnerability in the MediaWiki ExternalGuidance extension enabled users with the <tt>editinterface</tt> right, but without the <tt>editsitejs</tt>/<tt>editsitecss</tt> rights (notably, including the default <tt>sysop</tt> user-group), to execute arbitrary JavaScript in some end-users' web browsers, by overriding certain system messages which the ExternalGuidance extension inserted into the page as raw HTML.</p><p>The vulnerable system messages were:</p><ul><li><tt>externalguidance-machine-translation-heading</tt></li><li><tt>externalguidance-machine-translation-contribute</tt></li></ul><p></p><p>This issue affects all versions of the ExternalGuidance extension before Git commits <tt>c7c51ca611</tt> (branch <tt>master</tt>), before <tt>22986d5fd1</tt> (branch <tt>REL1_44</tt>), before <tt>c0a0d0e568</tt> (branch <tt>REL1_43</tt>), &amp; before <tt>3d6e2f673a</tt> (branch <tt>REL1_39</tt>).<br></p>"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://phabricator.wikimedia.org/T399662",
          "tags": [
            "issue-tracking"
          ]
        },
        {
          "url": "https://gerrit.wikimedia.org/r/c/mediawiki/extensions/ExternalGuidance/+/1189231",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://gerrit.wikimedia.org/r/c/mediawiki/extensions/ExternalGuidance/+/1189244",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://gerrit.wikimedia.org/r/c/mediawiki/extensions/ExternalGuidance/+/1193509",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://gerrit.wikimedia.org/r/c/mediawiki/extensions/ExternalGuidance/+/1193510",
          "tags": [
            "patch"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ],
          "cvssV4_0": {
            "version": "4.0",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "privilegesRequired": "HIGH",
            "userInteraction": "PASSIVE",
            "vulnConfidentialityImpact": "LOW",
            "subConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "vulnAvailabilityImpact": "NONE",
            "subAvailabilityImpact": "NONE",
            "Safety": "NOT_DEFINED",
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "valueDensity": "NOT_DEFINED",
            "vulnerabilityResponseEffort": "NOT_DEFINED",
            "providerUrgency": "NOT_DEFINED",
            "baseSeverity": "MEDIUM",
            "baseScore": 4.8,
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "SomeRandomDeveloper",
          "type": "finder"
        },
        {
          "lang": "en",
          "value": "SomeRandomDeveloper",
          "type": "remediation developer"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      },
      "workarounds": [
        {
          "lang": "en",
          "value": "Add the following lines to a MediaWiki installation's LocalSettings.php file:\n$wgRawHtmlMessages[] = \"externalguidance-machine-translation-heading\";\n$wgRawHtmlMessages[] = \"externalguidance-machine-translation-contribute\";",
          "supportingMedia": [
            {
              "type": "text/html",
              "base64": false,
              "value": "Add the following lines to a MediaWiki installation's LocalSettings.php file:\n<pre>$wgRawHtmlMessages[] = \"externalguidance-machine-translation-heading\";\n$wgRawHtmlMessages[] = \"externalguidance-machine-translation-contribute\";</pre>"
            }
          ]
        }
      ]
    }
  }
}