{"id":"CVE-2026-47138","summary":"Parse Server: Pre-authentication denial of service via client version header regex backtracking","details":"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.","aliases":["BIT-parse-2026-47138","GHSA-38m6-82c8-4xfm"],"modified":"2026-07-15T02:20:25.245150329Z","published":"2026-06-12T18:22:02.751Z","database_specific":{"cwe_ids":["CWE-1333"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47138.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47138.json"},{"type":"ADVISORY","url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-38m6-82c8-4xfm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-47138"},{"type":"FIX","url":"https://github.com/parse-community/parse-server/pull/10463"},{"type":"FIX","url":"https://github.com/parse-community/parse-server/pull/10464"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/parse-community/parse-server","events":[{"introduced":"0"},{"fixed":"baa153c49083a57f00790c3e418cd5d45961113f"},{"introduced":"532a461d30a6ed4457839f2caf5f30d5abf51a55"},{"fixed":"216cf8335b1612c6315cbb24cc9ecacfa94d7c66"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"8.6.77"},{"introduced":"9.0.0"},{"fixed":"9.9.1-alpha.1"}],"source":"AFFECTED_FIELD"}}],"versions":["9.9.0","8.6.76","9.8.0","8.6.75","9.7.0","8.6.74","8.6.73","8.6.72","8.6.71","8.6.70","9.6.1","8.6.69","8.6.68","8.6.67","8.6.66","8.6.65","8.6.64","8.6.63","8.6.62","9.6.0","9.5.1","8.6.61","8.6.60","8.6.59","8.6.58","8.6.57","8.6.56","8.6.55","8.6.54","8.6.53","8.6.52","8.6.51","8.6.50","8.6.49","8.6.48","8.6.47","8.6.46","8.6.45","8.6.44","8.6.43","8.6.42","8.6.41","8.6.40","8.6.39","8.6.38","8.6.37","8.6.36","8.6.35","8.6.34","8.6.33","8.6.32","8.6.31","8.6.30","8.6.29","8.6.28","8.6.27","8.6.26","8.6.25","8.6.24","8.6.23","8.6.22","8.6.21","8.6.20","8.6.19","8.6.18","8.6.17","8.6.16","8.6.15","8.6.14","8.6.13","9.5.0","8.6.12","8.6.11","9.4.1","8.6.10","8.6.9","8.6.8","8.6.7","8.6.6","8.6.5","8.6.4","9.4.0","8.6.3","9.3.1","9.3.0","8.6.2","9.2.0","9.1.1","9.1.0","8.6.1","9.0.0","8.6.0","8.5.0","8.4.0","8.3.0","8.2.5","8.2.4","8.2.3","8.2.2","8.2.1","8.2.0","8.1.0","8.0.2","8.0.1","8.0.0","7.4.0","7.3.0","7.2.0","7.1.0","7.0.0","6.4.0","6.3.1","6.3.0","6.2.2","6.2.1","6.2.0","6.1.0","6.0.0","5.4.0","5.3.3","5.3.2","5.3.1","5.3.0","5.2.8","5.2.7","5.2.6","5.2.5","5.2.4","5.2.3","5.2.2","5.2.1","5.2.0","5.1.1","5.1.0","5.0.0","5.0.0-alpha.1","4.5.0","4.4.0","4.3.0","4.2.0","4.1.0","4.0.2","4.0.1","4.0.0","3.10.0","3.9.0","3.8.0","3.7.2","3.7.1","3.7.0","3.6.0","3.5.0","3.4.0","3.4.1","3.3.0","3.2.3","3.2.2","3.2.1","3.2.0","3.1.3","3.1.2","3.1.1","3.1.0","3.0.0","2.8.2","2.8.0","2.7.4","2.7.3","2.7.2","2.7.1","2.7.0","2.6.5","2.6.4","2.6.3","2.6.2","2.6.1","2.6.0","2.5.3","2.5.2","2.5.1","2.5.0","2.4.2","2.4.1","2.4.0","2.3.8","2.3.7","2.3.6","2.3.5","2.3.4","2.3.3","2.3.2","2.3.1","2.2.25","2.2.25-beta.1","2.2.24","2.2.23","2.2.22","2.2.21","2.2.20","2.2.19","2.2.18","2.2.17","2.2.16","2.2.15","2.2.14","2.2.13","2.2.12","2.2.11","2.2.10","2.2.9","2.2.8","2.2.7","2.2.6","2.2.5","2.2.4","2.2.3","2.2.2","2.2.1","2.2.0","2.1.6","2.1.5","2.1.4","2.1.3","2.1.2","2.1.1","2.1.0","2.0.8","2.0.7","2.0.3","2.0.6","2.0.5","2.0.4","2.0.2","2.0.1","2.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-47138.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}