{"id":"CVE-2025-59830","summary":"Rack QueryParser has an unsafe default allowing params_limit bypass via semicolon-separated parameters","details":"Rack is a modular Ruby web server interface. Prior to version 2.2.18, Rack::QueryParser enforces its params_limit only for parameters separated by &, while still splitting on both & and ;. As a result, attackers could use ; separators to bypass the parameter count limit and submit more parameters than intended. Applications or middleware that directly invoke Rack::QueryParser with its default configuration (no explicit delimiter) could be exposed to increased CPU and memory consumption. This can be abused as a limited denial-of-service vector. This issue has been patched in version 2.2.18.","aliases":["GHSA-625h-95r8-8xpm"],"modified":"2026-04-16T04:36:30.756415047Z","published":"2025-09-25T14:37:06.967Z","related":["ALSA-2025:19719","ALSA-2025:20962","ALSA-2025:21036","CGA-8fhh-662x-5cqf","openSUSE-SU-2025:15587-1","openSUSE-SU-2026:10286-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/59xxx/CVE-2025-59830.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-400","CWE-770"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/59xxx/CVE-2025-59830.json"},{"type":"ADVISORY","url":"https://github.com/rack/rack/security/advisories/GHSA-625h-95r8-8xpm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-59830"},{"type":"FIX","url":"https://github.com/rack/rack/commit/54e4ffdd5affebcb0c015cc6ae74635c0831ed71"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/rack/rack","events":[{"introduced":"0"},{"fixed":"0f76d43c0d5624bd0d325df4f0a63f5e1faa7254"}]}],"versions":["0.1","0.2","0.3","1.0","1.3.0","1.3.0.beta","1.3.0.beta2","1.4.0","1.4.1","1.5.0","1.5.1","1.6.0.beta","2.0.0","2.0.0.alpha","2.0.0.rc1","2.0.1","2.1.0","2.2.0","2.2.3","2.2.4","v2.2.1","v2.2.10","v2.2.11","v2.2.12","v2.2.13","v2.2.14","v2.2.15","v2.2.16","v2.2.17","v2.2.2","v2.2.5","v2.2.6","v2.2.6.1","v2.2.6.2","v2.2.7","v2.2.8","v2.2.9"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-59830.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}