CVE-2026-53724 Parse Server: Stored XSS via trailing-dot filename bypassing file upload extension blocklist

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...

Parse Server: File upload Content-Type override via extension mismatch

Impact A file can be uploaded with a filename extension that passes the file extension allowlist e.g., .txt but with a Content-Type header that differs from the extension e.g., text/html. The Content-Type is passed to the storage adapter without consistency validation. Storage adapters that store...