CVE-2026-34829 (GCVE-0-2026-34829)
Vulnerability from cvelistv5
Published
2026-04-02 16:46
Modified
2026-04-02 17:41
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Summary
Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser only wraps the request body in a BoundedIO when CONTENT_LENGTH is present. When a multipart/form-data request is sent without a Content-Length header, such as with HTTP chunked transfer encoding, multipart parsing continues until end-of-stream with no total size limit. For file parts, the uploaded body is written directly to a temporary file on disk rather than being constrained by the buffered in-memory upload limit. An unauthenticated attacker can therefore stream an arbitrarily large multipart file upload and consume unbounded disk space. This results in a denial of service condition for Rack applications that accept multipart form data. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.
Impacted products
Vendor Product Version
rack rack Version: < 2.2.23
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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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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