Executive brief
Parse Server is an open-source backend framework used to build and host applications. A vulnerability in how it handles complex database queries allows an attacker to send a specially crafted request that overwhelms the server's processor. This can lead to a complete service outage, making the application unavailable to legitimate users.
Technical details
A denial-of-service (DoS) vulnerability exists in Parse Server due to inefficient algorithmic complexity (CWE-407) in its query-traversal helper. Specifically, the internal logic for handling deeply nested logical operators ($or, $and, $nor) in REST API or LiveQuery requests can trigger exponential-time processing. Because Node.js is single-threaded, this processing blocks the event loop, preventing the server from handling any other concurrent requests. An unauthenticated remote attacker can exploit this by submitting a query with high nesting depth. The issue is mitigated in patched versions by implementing query depth limits and optimizing the traversal logic. Fixes are available in versions 9.9.1-alpha.12 and 8.6.82.
Affected products
- Parse Community Parse Server >= 9.0.0-alpha.1, < 9.9.1-alpha.12; < 8.6.82
Timeline
- 2026-06-17: patched: Fixes committed to repository
- 2026-07-08: disclosed: CVE-2026-57480 published
References
- https://github.com/parse-community/parse-server/commit/0f5d2ad77b422dc904458254548be87397fc6e9b
- https://github.com/parse-community/parse-server/commit/1103c7a890e0455ba3dccd4bc5db17efe1789c9a
- https://github.com/parse-community/parse-server/pull/10511
- https://github.com/parse-community/parse-server/pull/10512
- https://github.com/parse-community/parse-server/releases/tag/8.6.82
- https://github.com/parse-community/parse-server/releases/tag/9.9.1-alpha.12
- https://github.com/parse-community/parse-server/security/advisories/GHSA-cgxm-vr2f-6fj8