CVE-2026-30925

The record

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.0-alpha.14 and 8.6.11, 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. This vulnerability is fixed in 9.5.0-alpha.14 and 8.6.11.

Affected packages

Related vulnerabilities

• GHSA-mf3j-86qx-cq5j Parse Server has Regular Expression Denial of Service (ReDoS) via `$regex` query in… Same vulnerability
• GHSA-97pr-9hgg-3p8r parse-server: LiveQuery discloses object data to a subscriber across an ACL read-access… Also affects parse-server
• GHSA-wmwx-jr2p-4j4r parse-server: Relation `$relatedTo` query bypasses `protectedFields` and owning-object ACL Also affects parse-server
• GHSA-7wqv-xjf3-x35v parse-server: Stored XSS via trailing-dot filename bypassing file upload extension… Also affects parse-server
• GHSA-p84r-h6rx-f2xr parse-server: Server option routeAllowList is bypassable through batch sub-requests Also affects parse-server
• GHSA-cgxm-vr2f-6fj8 parse-server: Denial of service via exponential-time processing of deeply nested query… Also affects parse-server
• CVE-2026-53726 Parse Server is an open source backend that can be deployed to any infrastructure that… Also affects parse-server
• CVE-2026-53724 Parse Server is an open source backend that can be deployed to any infrastructure that… Also affects parse-server