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.
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Thu, 25 Sep 2025 17:15:00 +0000
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Thu, 25 Sep 2025 15:00:00 +0000
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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. | |
Title | Rack QueryParser has an unsafe default allowing params_limit bypass via semicolon-separated parameters | |
Weaknesses | CWE-400 CWE-770 |
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cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2025-09-25T16:16:15.255Z
Reserved: 2025-09-22T14:34:03.471Z
Link: CVE-2025-59830

Updated: 2025-09-25T16:16:11.658Z

Status : Received
Published: 2025-09-25T15:16:13.780
Modified: 2025-09-25T15:16:13.780
Link: CVE-2025-59830

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