CVE-2026-35200
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
Vulnerability in Parse Server before versions 8.6.73 and 9.7.1-alpha.4 allowing file upload with a valid extension but mismatched Content-Type header. Some storage adapters (S3, GCS) serve the file with the provided Content-Type, potentially leading to attacks.
Risk Assessment
An attacker can upload a file that is served as HTML, potentially leading to XSS or other attacks on users.
Recommendation
Update Parse Server to version 8.6.73 or 9.7.1-alpha.4 (or later).
Original NVD description (English source)
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 8.6.73 and 9.7.1-alpha.4, 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 and serve the provided Content-Type (such as S3 or GCS) serve the file with the mismatched Content-Type. The default GridFS adapter is not affected because it derives Content-Type from the filename at serving time. This vulnerability is fixed in 8.6.73 and 9.7.1-alpha.4.