CVE-2026-30925: Parse Server has Regular Expression Denial of Service (ReDoS) via `$regex` query in LiveQuery
A malicious client can subscribe to a LiveQuery with a crafted $regex pattern that causes catastrophic backtracking, blocking the Node.js event loop. This makes the entire Parse Server unresponsive, affecting all clients. Any Parse Server deployment with LiveQuery enabled is affected. The attacker only needs the application ID and JavaScript key, both of which are public in client-side apps.
This only affects LiveQuery subscription matching, which evaluates regex in JavaScript on the Node.js event loop. Normal REST and GraphQL queries are not affected because their regex is evaluated by the database engine.
References
- github.com/advisories/GHSA-mf3j-86qx-cq5j
- github.com/parse-community/parse-server
- github.com/parse-community/parse-server/releases/tag/8.6.11
- github.com/parse-community/parse-server/releases/tag/9.5.0-alpha.14
- github.com/parse-community/parse-server/security/advisories/GHSA-mf3j-86qx-cq5j
- nvd.nist.gov/vuln/detail/CVE-2026-30925
Code Behaviors & Features
Detect and mitigate CVE-2026-30925 with GitLab Dependency Scanning
Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →