{"id":"GHSA-7wqv-xjf3-x35v","revision":"5c40d1faceec447fb905dbec08ccfc67","records":[{"revision":"5c40d1faceec447fb905dbec08ccfc67","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-7wqv-xjf3-x35v","aliases":["BIT-parse-2026-53724","CVE-2026-53724"],"title":"parse-server: Stored XSS via trailing-dot filename bypassing file upload extension blocklist","description":"### Impact\n\nThe 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.\n\n### Patches\n\nA filename ending in a dot is now treated as extensionless. When the parser produces an empty extension, the request handler falls back to validating the Content-Type subtype against the configured extension blocklist, matching the path that already catches truly extensionless uploads with a dangerous Content-Type. This is a follow-up to the previous fix [GHSA-vr5f-2r24-w5hc](https://github.com/parse-community/parse-server/security/advisories/GHSA-vr5f-2r24-w5hc).\n\n### Workarounds\n\nConfigure the storage adapter or CDN to derive Content-Type from the filename extension instead of using the stored Content-Type, or replace the default blocklist with an explicit allowlist of needed file extensions.","state":0,"publishedAt":"2026-06-19T19:35:11+00:00","modifiedAt":"2026-06-19T19:56:23.1246478+00:00","affected":[{"ecosystem":"npm","name":"parse-server","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"9.0.0"},{"kind":"fixed","version":"9.9.1-alpha.4"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"npm","name":"parse-server","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"8.6.79"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V4","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":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"LOW"}],"references":["https://github.com/parse-community/parse-server/security/advisories/GHSA-7wqv-xjf3-x35v","https://nvd.nist.gov/vuln/detail/CVE-2026-53724","https://github.com/parse-community/parse-server/pull/10489","https://github.com/parse-community/parse-server/pull/10490","https://github.com/parse-community/parse-server"],"sourceUrl":"https://github.com/advisories/GHSA-7wqv-xjf3-x35v","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-7wqv-xjf3-x35v","identifiers":["GHSA-7wqv-xjf3-x35v","BIT-parse-2026-53724","CVE-2026-53724"]},"retained":false,"historicalAffected":[]}],"coverage":[]}