{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-77987", "assignerOrgId": "82327ea3-741d-41e4-88f8-2cf9e791e760", "state": "PUBLISHED", "assignerShortName": "GitHub_P", "dateReserved": "2026-08-21T18:51:48.052Z", "datePublished": "2026-09-22T20:43:53.715Z", "dateUpdated": "2026-09-22T20:43:53.715Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "82327ea3-741d-41e4-88f8-2cf9e791e760", "shortName": "GitHub_P", "dateUpdated": "2026-09-22T20:43:53.715Z"}, "title": "GitHub Enterprise Server notebook viewer vulnerable to Server-side request forgery", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-918", "description": "CWE-918 Server-Side Request Forgery (SSRF)", "type": "CWE"}, {"lang": "en", "cweId": "CWE-208", "description": "CWE-208 Observable Timing Discrepancy", "type": "CWE"}]}], "impacts": [{"capecId": "CAPEC-664", "descriptions": [{"lang": "en", "value": "CAPEC-664 Server Side Request Forgery"}]}, {"capecId": "CAPEC-462", "descriptions": [{"lang": "en", "value": "CAPEC-462 Cross-Domain Search Timing"}]}], "affected": [{"vendor": "GitHub", "product": "Enterprise Server", "versions": [{"status": "affected", "version": "3.17.0", "lessThan": "3.17.*", "changes": [{"at": "3.17.21", "status": "unaffected"}], "versionType": "semver"}, {"status": "affected", "version": "3.18.0", "lessThan": "3.18.*", "changes": [{"at": "3.18.15", "status": "unaffected"}], "versionType": "semver"}, {"status": "affected", "version": "3.19.0", "lessThan": "3.19.*", "changes": [{"at": "3.19.12", "status": "unaffected"}], "versionType": "semver"}, {"status": "affected", "version": "3.20.0", "lessThan": "3.20.*", "changes": [{"at": "3.20.8", "status": "unaffected"}], "versionType": "semver"}, {"status": "affected", "version": "3.21.0", "lessThan": "3.21.*", "changes": [{"at": "3.21.6", "status": "unaffected"}], "versionType": "semver"}, {"status": "affected", "version": "3.22.0", "lessThan": "3.22.*", "changes": [{"at": "3.22.1", "status": "unaffected"}], "versionType": "semver"}], "defaultStatus": "unknown"}], "descriptions": [{"lang": "en", "value": "A server-side request forgery (SSRF) vulnerability was identified in the notebook viewer of GitHub Enterprise Server. 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