{"cve":"CVE-2025-59830","nvd":{"published":"2025-09-25T15:16:13.780","modified":"2026-10-19T16:10:00.260","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400","CWE-770"],"references":["https://github.com/rack/rack/commit/54e4ffdd5affebcb0c015cc6ae74635c0831ed71","https://github.com/rack/rack/security/advisories/GHSA-625h-95r8-8xpm"],"products":["rack:rack"],"source":"nvd","synced_at":"2026-10-19T22:10:08.713834912+00:00"},"epss":{"cve":"CVE-2025-59830","score":0.00573,"percentile":0.47086,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-625h-95r8-8xpm","url":"https://osv.dev/vulnerability/GHSA-625h-95r8-8xpm","summary":"Rack has an unsafe default in Rack::QueryParser allows params_limit bypass via semicolon-separated parameters","modified":"2026-09-10T03:50:58.118464536Z","packages":[{"ecosystem":"RubyGems","name":"rack","purl":"pkg:gem/rack","ranges":["<2.2.18"],"fixed":["2.2.18"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}