Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| rack / rack | affected >= 3.0.0.beta1, < 3.1.21; affected >= 3.2.0, < 3.2.6 |
CWE
CWE-407, CWE-400, CWE-770
References
ADP enrichment
No English description supplied.
No references supplied.
A flaw was found in Rack, a modular Ruby web server interface. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted multipart/form-data request. This request, containing numerous parts with lengthy backslash-escaped parameter values, causes the system to consume excessive CPU resources during parsing. This algorithmic complexity issue ultimately leads to a denial of service (DoS) condition in Rack applications that process multipart form data.