{"id":"CVE-2026-34573","aliases":["BIT-parse-2026-34573","EUVD-2026-17500","GHSA-mfj6-6p54-m98c"],"status":"published","title":"Parse Server: GraphQL complexity validator exponential fragment traversal DoS","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.","severity":{"version":"4.0","score":8.2,"vector":"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00643,"percentile":0.51096,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-407"],"published":"2026-03-31T15:06:33Z","modified":"2026-10-28T02:30:50Z","fixes":[{"ecosystem":"npm","package":"parse-server","fixed_in":["9.7.0-alpha.12","8.6.68"],"sources":["ghsa","osv"]},{"ecosystem":"Bitnami","package":"parse","fixed_in":["8.6.68","9.7.0"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"parse-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"9.0.0"},{"fixed":"9.7.0-alpha.12"}]}]},{"source":"ghsa","ecosystem":"npm","package":"parse-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.6.68"}]}]},{"source":"osv","ecosystem":"Bitnami","package":"parse","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"8.6.68"},{"introduced":"9.0.0"},{"fixed":"9.7.0"}]}]},{"source":"osv","ecosystem":"npm","package":"parse-server","ranges":[{"type":"SEMVER","events":[{"introduced":"9.0.0"},{"fixed":"9.7.0-alpha.12"}]}]},{"source":"osv","ecosystem":"npm","package":"parse-server","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"8.6.68"}]}]}],"products":[{"vendor":"parse-community","product":"parse-server"},{"vendor":"parseplatform","product":"parse-server"}],"references":[{"url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c","tags":["x_refsource_CONFIRM","Patch","Vendor Advisory","advisory","web"]},{"url":"https://github.com/parse-community/parse-server/pull/10344","tags":["x_refsource_MISC","Issue Tracking","Patch","fix","web"]},{"url":"https://github.com/parse-community/parse-server/pull/10345","tags":["x_refsource_MISC","Issue Tracking","Patch","fix","web"]},{"url":"https://github.com/parse-community/parse-server/commit/ea15412795f34594cc8a674fe858d445675e0295","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/parse-community/parse-server/commit/f759bda075298ec44e2b4fb57659a0c56620483b","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34573","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-mfj6-6p54-m98c"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34573.json","tags":["advisory"]},{"url":"https://github.com/parse-community/parse-server","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-34573","title":"Parse Server: GraphQL complexity validator exponential fragment traversal DoS","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.","status":"published","published":"2026-03-31T15:06:33.372Z","modified":"2026-03-31T18:52:50.211Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high","assessor":"cna"}],"cwes":["CWE-407"],"updated_at":"2026-11-02T14:20:14.665567Z"}],"euvd":[{"id":"EUVD-2026-17500","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.","status":"published","published":"2026-03-31T15:06:33Z","modified":"2026-03-31T18:52:50Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"updated_at":"2026-11-02T19:25:24.891983Z"}],"ghsa":[{"id":"GHSA-mfj6-6p54-m98c","title":"parse-server has GraphQL complexity validator exponential fragment traversal DoS","description":"### Impact\n\nThe 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.\n\n### Patches\n\nThe 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.\n\n### Workarounds\n\nDisable GraphQL complexity limits by setting `requestComplexity.graphQLDepth` and `requestComplexity.graphQLFields` to `-1` (the default).\n\n### Resources\n\n- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c\n- Fix Parse Server 9: https://github.com/parse-community/parse-server/pull/10344\n- Fix Parse Server 8: https://github.com/parse-community/parse-server/pull/10345","status":"published","published":"2026-03-31T23:49:18Z","modified":"2026-03-31T23:49:19Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"cwes":["CWE-407"],"updated_at":"2026-11-02T14:39:47.075804Z"}],"nvd":[{"id":"CVE-2026-34573","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.","status":"published","published":"2026-03-31T16:16:33.737Z","modified":"2026-07-24T20:10:00.147Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-407"],"updated_at":"2026-11-02T14:12:12.261218Z"}],"osv":[{"id":"CVE-2026-34573","title":"Parse Server: GraphQL complexity validator exponential fragment traversal DoS","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.","status":"published","published":"2026-03-31T15:06:33.372Z","modified":"2026-10-28T02:30:50.977502727Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"cwes":["CWE-407"],"updated_at":"2026-11-02T15:45:02.247031Z"},{"id":"GHSA-mfj6-6p54-m98c","title":"parse-server has GraphQL complexity validator exponential fragment traversal DoS","description":"### Impact\n\nThe 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.\n\n### Patches\n\nThe 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.\n\n### Workarounds\n\nDisable GraphQL complexity limits by setting `requestComplexity.graphQLDepth` and `requestComplexity.graphQLFields` to `-1` (the default).\n\n### Resources\n\n- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-mfj6-6p54-m98c\n- Fix Parse Server 9: https://github.com/parse-community/parse-server/pull/10344\n- Fix Parse Server 8: https://github.com/parse-community/parse-server/pull/10345","status":"published","published":"2026-03-31T23:49:18Z","modified":"2026-04-06T15:27:07.040958679Z","cvss":[{"version":"4.0","score":8.2,"vector":"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","level":"high"}],"cwes":["CWE-407"],"updated_at":"2026-11-02T15:46:51.811331Z"},{"id":"BIT-parse-2026-34573","title":"Parse Server: GraphQL complexity validator exponential fragment traversal DoS","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, 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.","status":"published","published":"2026-04-06T14:49:33.069Z","modified":"2026-09-08T08:48:17.748264872Z","updated_at":"2026-11-02T15:28:34.343258Z"}]}}