CVE-2026-34827 (GCVE-0-2026-34827)
Vulnerability from cvelistv5
Published
2026-04-02 17:07
Modified
2026-04-03 18:13
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Summary
Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21, and 3.2.0 to before 3.2.6, Rack::Multipart::Parser#handle_mime_head parses quoted multipart parameters such as Content-Disposition: form-data; name="..." using repeated String#index searches combined with String#slice! prefix deletion. For escape-heavy quoted values, this causes super-linear processing. An unauthenticated attacker can send a crafted multipart/form-data request containing many parts with long backslash-escaped parameter values to trigger excessive CPU usage during multipart parsing. This results in a denial of service condition in Rack applications that accept multipart form data. This issue has been patched in versions 3.1.21 and 3.2.6.
Impacted products
Vendor Product Version
rack rack Version: >= 3.0.0.beta1, < 3.1.21
Version: >= 3.2.0, < 3.2.6
Create a notification for this product.
Show details on NVD website


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