CVE-2025-61919 (GCVE-0-2025-61919)

Vulnerability from cvelistv5 – Published: 2025-10-10 19:22 – Updated: 2025-10-10 20:48
VLAI
Title
Rack is vulnerable to a memory-exhaustion DoS through unbounded URL-encoded body parsing
Summary
Rack is a modular Ruby web server interface. Prior to versions 2.2.20, 3.1.18, and 3.2.3, `Rack::Request#POST` reads the entire request body into memory for `Content-Type: application/x-www-form-urlencoded`, calling `rack.input.read(nil)` without enforcing a length or cap. Large request bodies can therefore be buffered completely into process memory before parsing, leading to denial of service (DoS) through memory exhaustion. Users should upgrade to Rack version 2.2.20, 3.1.18, or 3.2.3, anu of which enforces form parameter limits using `query_parser.bytesize_limit`, preventing unbounded reads of `application/x-www-form-urlencoded` bodies. Additionally, enforce strict maximum body size at the proxy or web server layer (e.g., Nginx `client_max_body_size`, Apache `LimitRequestBody`).
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-10 20:48 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7895 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rack rack Affected: < 2.2.20
Affected: >= 3.0, < 3.1.18
Affected: >= 3.2, < 3.2.3
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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