CVE-2026-34573
Medium
Elevated severity or exploit probability.
CVSS base
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS — probability of exploitation (30 days)
0.9%
56.6th percentile
CISA KEV
Not listed
Weakness / dates
CWE-407
Published 2026-03-31 · modified 2026-07-24
Description
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.68 and 9.7.0-alpha.12, the GraphQL query complexity validator can be exploited to cause a denial-of-service by sending a crafted query with binary fan-out fragment spreads. A single unauthenticated request can block the Node.js event loop for seconds, denying service to all concurrent users. This only affects deployments that have enabled the requestComplexity.graphQLDepth or requestComplexity.graphQLFields configuration options. This issue has been patched in versions 8.6.68 and 9.7.0-alpha.12.
Affected
References
- https://github.com/parse-community/parse-server/commit/ea15412795f34594cc8a674fe858d445675e0295
- https://github.com/parse-community/parse-server/commit/f759bda075298ec44e2b4fb57659a0c56620483b
- https://github.com/parse-community/parse-server/pull/10344
- https://github.com/parse-community/parse-server/pull/10345
- https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c