CVE-2026-55778
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.
- Score
- CVSS 4.0 2.1 Low
- Status
- Deferred - security-advisories@github.com
- Published
- 2026-07-08
- Last modified
- 2026-10-25
- Weaknesses
- CWE-434
Affected products
References
- https://github.com/parse-community/parse-server/security/advisories/GHSA-v8x7-r927-cc93
- https://github.com/parse-community/parse-server/pull/10505
- https://github.com/parse-community/parse-server/pull/10506
- https://github.com/parse-community/parse-server/commit/97c6a78d19f976ec756c1295f08a8fccab90799a
- https://github.com/parse-community/parse-server/commit/be12a60d65b6e140481882037fb896b1f951df50
- https://github.com/parse-community/parse-server/releases/tag/8.6.81
- https://github.com/parse-community/parse-server/releases/tag/9.9.1-alpha.11
