{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-55778","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-06-17T14:40:28.379Z","datePublished":"2026-07-08T20:50:52.531Z","dateUpdated":"2026-07-09T13:39:44.881Z"},"containers":{"cna":{"title":"Parse Server: Stored XSS via non-standard file extension bypassing file upload extension blocklist","problemTypes":[{"descriptions":[{"cweId":"CWE-434","lang":"en","description":"CWE-434: Unrestricted Upload of File with Dangerous Type","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","subAvailabilityImpact":"NONE","baseScore":2.1,"baseSeverity":"LOW","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/parse-community/parse-server/security/advisories/GHSA-v8x7-r927-cc93","tags":["x_refsource_CONFIRM"],"url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-v8x7-r927-cc93"},{"name":"https://github.com/parse-community/parse-server/pull/10505","tags":["x_refsource_MISC"],"url":"https://github.com/parse-community/parse-server/pull/10505"},{"name":"https://github.com/parse-community/parse-server/pull/10506","tags":["x_refsource_MISC"],"url":"https://github.com/parse-community/parse-server/pull/10506"},{"name":"https://github.com/parse-community/parse-server/commit/97c6a78d19f976ec756c1295f08a8fccab90799a","tags":["x_refsource_MISC"],"url":"https://github.com/parse-community/parse-server/commit/97c6a78d19f976ec756c1295f08a8fccab90799a"},{"name":"https://github.com/parse-community/parse-server/commit/be12a60d65b6e140481882037fb896b1f951df50","tags":["x_refsource_MISC"],"url":"https://github.com/parse-community/parse-server/commit/be12a60d65b6e140481882037fb896b1f951df50"},{"name":"https://github.com/parse-community/parse-server/releases/tag/8.6.81","tags":["x_refsource_MISC"],"url":"https://github.com/parse-community/parse-server/releases/tag/8.6.81"},{"name":"https://github.com/parse-community/parse-server/releases/tag/9.9.1-alpha.11","tags":["x_refsource_MISC"],"url":"https://github.com/parse-community/parse-server/releases/tag/9.9.1-alpha.11"}],"affected":[{"vendor":"parse-community","product":"parse-server","versions":[{"version":">= 9.0.0-alpha.1, < 9.9.1-alpha.11","status":"affected"},{"version":"< 8.6.81","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-07-08T20:50:52.531Z"},"descriptions":[{"lang":"en","value":"Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.9.1-alpha.11 and 8.6.81, the default fileUpload.fileExtensions blocklist could be bypassed by uploading a file with a non-standard or compound extension and dangerous content type, allowing storage adapters such as S3 and GCS to serve attacker-supplied active content and enable stored cross-site scripting. This issue is fixed in versions 9.9.1-alpha.11 and 8.6.81."}],"source":{"advisory":"GHSA-v8x7-r927-cc93","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-09T13:39:32.908358Z","id":"CVE-2026-55778","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-09T13:39:44.881Z"}}]}}