---
id: CVE-2026-34573
title: >-
  Parse Server is an open source backend that can be deployed to any
  infrastructure that can run Node.js
summary: >-
  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 …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-407
vendor: parseplatform
product: parse-server
affected:
  - parse-server < 8.6.68
  - 'parse-server >= 9.0.0, < 9.7.0'
  - parse-server = 9.7.0
patched:
  - parse-server 9.7.0
published: '2026-03-31'
updated: '2026-07-24'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-34573'
references:
  - url: >-
      https://github.com/parse-community/parse-server/commit/ea15412795f34594cc8a674fe858d445675e0295
    label: security-advisories@github.com
  - url: >-
      https://github.com/parse-community/parse-server/commit/f759bda075298ec44e2b4fb57659a0c56620483b
    label: security-advisories@github.com
  - url: 'https://github.com/parse-community/parse-server/pull/10344'
    label: security-advisories@github.com
  - url: 'https://github.com/parse-community/parse-server/pull/10345'
    label: security-advisories@github.com
  - url: >-
      https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c
    label: security-advisories@github.com
tags:
  - nvd
epss: 0.00856
epssPercentile: 0.5662
ingestedAt: '2026-07-24T20:38:02.544Z'
---

## Overview

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

- `parse-server < 8.6.68`
- `parse-server >= 9.0.0, < 9.7.0`
- `parse-server = 9.7.0`

## Remediation

Upgrade past the affected range:

- `parse-server 9.7.0`