CVE-2026-34573Parse Server: GraphQL complexity validator exponential fragment traversal DoS
- 8.2HighCVSS base score
- 0.64%Exploitation in 30 daysEPSS · top 49% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By GitHub_M
- 1 day later
· 1 day later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High8.2 | 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 |
| NVDNVD · Analyzed | 4.0 | High8.2 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.64% · top 49% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.2.
Affected products
parse-community · parse-server
- affected < 8.6.68
- affected >= 9.0.0, < 9.7.0-alpha.12
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npmparse-serverGHSA-mfj6-6p54-m98c (opens in a new tab)
References
References5
- https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c (opens in a new tab)x_refsource_CONFIRM
- https://github.com/parse-community/parse-server/pull/10344 (opens in a new tab)x_refsource_MISC
- https://github.com/parse-community/parse-server/pull/10345 (opens in a new tab)x_refsource_MISC
- https://github.com/parse-community/parse-server/commit/ea15412795f34594cc8a674fe858d445675e0295 (opens in a new tab)x_refsource_MISC
- https://github.com/parse-community/parse-server/commit/f759bda075298ec44e2b4fb57659a0c56620483b (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-17500 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-mfj6-6p54-m98c (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-34573)Record last updated .