{"id":"CVE-2026-53724","revision":"5ca5e01be51a4ff28a044663c3d8c928","records":[{"revision":"5ca5e01be51a4ff28a044663c3d8c928","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-53724","aliases":[],"title":"Parse Server: Stored XSS via trailing-dot filename bypassing file upload extension blocklist","description":"Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.79 and 9.9.1-alpha.4, the default file upload extension blocklist can be bypassed by appending a trailing dot to a filename whose extension would otherwise be blocked (e.g. poc.svg.). The trailing dot causes the extension parser to extract an empty string, which short-circuits the blocklist check, and the attacker-controlled Content-Type is forwarded to the storage adapter unchanged. Storage adapters that persist and serve the provided Content-Type (such as S3 or GCS) then serve the file with an active type such as image/svg+xml, enabling stored XSS when a victim opens the file URL. The default GridFS adapter is not affected because it sets X-Content-Type-Options: nosniff on responses. This issue has been patched in versions 8.6.79 and 9.9.1-alpha.4.","state":0,"publishedAt":"2026-06-12T18:34:38.237+00:00","modifiedAt":"2026-06-12T20:01:13.569+00:00","affected":[{"ecosystem":"Vendor product","name":"parse-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"parse-community\",\n                    \"product\": \"parse-server\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 8.6.79\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 9.0.0, < 9.9.1-alpha.4\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"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","score":2.1,"severity":"LOW"}],"references":["https://github.com/parse-community/parse-server/security/advisories/GHSA-7wqv-xjf3-x35v","https://github.com/parse-community/parse-server/pull/10489","https://github.com/parse-community/parse-server/pull/10490"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53724","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-53724","identifiers":["CVE-2026-53724"]},"retained":false,"historicalAffected":[]}],"coverage":[]}