GHSA-mfj6-6p54-m98c

parse-server has GraphQL complexity validator exponential fragment traversal DoS

At a glance

Published
Updated
CVE
CVE-2026-34573
Aliases
BIT-parse-2026-34573
CVSS_V4
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Description

### Impact 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. ### Patches The fix replaces the per-branch fragment traversal with memoized fragment computation, reducing the traversal from exponential O(2^N) to linear O(N) time. Additionally, early termination aborts the traversal as soon as configured limits are exceeded. ### Workarounds Disable GraphQL complexity limits by setting `requestComplexity.graphQLDepth` and `requestComplexity.graphQLFields` to `-1` (the default). ### Resources - GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c - Fix Parse Server 9: https://github.com/parse-community/parse-server/pull/10344 - Fix Parse Server 8: https://github.com/parse-community/parse-server/pull/10345

Affected packages

PackageVersions
npm · parse-serverintroduced 9.0.0, fixed 9.7.0-alpha.12
npm · parse-serverintroduced 0, fixed 8.6.68

References

Sources

SourceLicence
OSV.devCC-BY 4.0 — GitHub Advisory Database