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7.5
HIGH CVSS 3.1
CVE-2025-59830
Rack QueryParser has an unsafe default allowing params_limit bypass via semicolon-separated parameters
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.

INFO

Published Date :

Sept. 25, 2025, 3:16 p.m.

Last Modified :

Sept. 25, 2025, 3:16 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2025-59830 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Rack rack
: Total Affected Vendor : 1 | Products : 1
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update Rack to version 2.2.18 or later to fix a denial-of-service vulnerability.
  • Update Rack to version 2.2.18.
  • Apply the patch to Rack.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-59830.

URL Resource
https://github.com/rack/rack/commit/54e4ffdd5affebcb0c015cc6ae74635c0831ed71
https://github.com/rack/rack/security/advisories/GHSA-625h-95r8-8xpm
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-59830 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-59830 weaknesses.

CAPEC-147: XML Ping of the Death XML Ping of the Death CAPEC-227: Sustained Client Engagement Sustained Client Engagement CAPEC-492: Regular Expression Exponential Blowup Regular Expression Exponential Blowup CAPEC-125: Flooding Flooding CAPEC-130: Excessive Allocation Excessive Allocation CAPEC-147: XML Ping of the Death XML Ping of the Death CAPEC-197: Exponential Data Expansion Exponential Data Expansion CAPEC-229: Serialized Data Parameter Blowup Serialized Data Parameter Blowup CAPEC-230: Serialized Data with Nested Payloads Serialized Data with Nested Payloads CAPEC-231: Oversized Serialized Data Payloads Oversized Serialized Data Payloads CAPEC-469: HTTP DoS HTTP DoS CAPEC-482: TCP Flood TCP Flood CAPEC-486: UDP Flood UDP Flood CAPEC-487: ICMP Flood ICMP Flood CAPEC-488: HTTP Flood HTTP Flood CAPEC-489: SSL Flood SSL Flood CAPEC-490: Amplification Amplification CAPEC-491: Quadratic Data Expansion Quadratic Data Expansion CAPEC-493: SOAP Array Blowup SOAP Array Blowup CAPEC-494: TCP Fragmentation TCP Fragmentation CAPEC-495: UDP Fragmentation UDP Fragmentation CAPEC-496: ICMP Fragmentation ICMP Fragmentation CAPEC-528: XML Flood XML Flood

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-59830 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2025-59830 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 25, 2025

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-400
    Added CWE CWE-770
    Added Reference https://github.com/rack/rack/commit/54e4ffdd5affebcb0c015cc6ae74635c0831ed71
    Added Reference https://github.com/rack/rack/security/advisories/GHSA-625h-95r8-8xpm
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact