CVE-2026-34573highCWE-407

CVE-2026-34573: high-severity vulnerability in parse-community parse-server

Parse Server: GraphQL complexity validator exponential fragment traversal DoS

Published

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.2epss 0.9%
exploitation probability
0.9%top 43% of all CVEs
observed exploitation
nono source reports it
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.
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
Affected products
parse-community · parse-server
Related CVEs — parse-community parse-server

In the same product, most dangerous first.

CVE-2022-24760CRITICALCommand Injection in Parse serverEPSS 49.1%CVE-2022-39396CRITICALParse Server vulnerable to Remote Code Execution via prototype pollution in MongoDB BSON parserEPSS 38.7%CVE-2024-39309CRITICALZDI-CAN-23894: Parse Server literalizeRegexPart SQL Injection Authentication Bypass VulnerabilityEPSS 20.2%CVE-2023-36475CRITICALParse Server vulnerable to remote code execution via MongoDB BSON parser through prototype pollutionEPSS 3.2%CVE-2021-39187HIGHCrash server with query parameterEPSS 1.8%CVE-2026-30965CRITICALParse Server session token exfiltration via `redirectClassNameForKey` query parameterEPSS 1.6%
References
https://github.com/parse-community/parse-server/commit/ea15412795f34594cc8a674fe858d445675e0295https://github.com/parse-community/parse-server/commit/f759bda075298ec44e2b4fb57659a0c56620483bhttps://github.com/parse-community/parse-server/pull/10344https://github.com/parse-community/parse-server/pull/10345https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c