CVE-2025-59830

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.

Affected products

Almalinux, Centos, Debian, Linuxmint, Rack, Red Hat, Red Os, Rocky Linux

Rack

< 2.2.18

Fix

Available

CVSS 3.1

7.5 HIGH

EPSS

0.5% (42th percentile)

Weakness

CWE-400, CWE-770

NVD status

Analyzed

Published

2025-09-25

No exploit for CVE-2025-59830 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.