CVE-2026-47138
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.77 and 9.9.1-alpha.1, an unauthenticated attacker who knows a publicly-known Parse Application ID can submit a single HTTP request whose client SDK version field contains adversarial input that triggers polynomial backtracking in a request-header parser. The parsing runs before session authentication and before rate limiting on every /parse/* request, so the request consumes seconds to minutes of synchronous CPU on a Node.js worker before any access control evaluates it. A small number of concurrent requests can saturate a worker; a single large request via the body-field variant can pin a worker for minutes. Production deployments running the default configuration are affected. This issue has been patched in versions 8.6.77 and 9.9.1-alpha.1.
- Score
- CVSS 4.0 8.7 High
- Status
- Deferred - security-advisories@github.com
- Published
- 2026-06-12
- Last modified
- 2026-10-26
- Weaknesses
- CWE-1333
Affected products
References
- https://github.com/parse-community/parse-server/security/advisories/GHSA-38m6-82c8-4xfm
- https://github.com/parse-community/parse-server/pull/10463
- https://github.com/parse-community/parse-server/pull/10464
