Rack · Rack · CVE-2025-61770
**Name of the Vulnerable Software and Affected Versions**
Rack versions prior to 2.2.19
Rack versions prior to 3.1.17
Rack versions prior to 3.2.2
**Description**
Rack is a modular Ruby web server interface. The `Rack::Multipart::Parser` component does not limit the size of the multipart preamble, potentially leading to excessive memory consumption and process termination due to out-of-memory conditions. An attacker can send a large preamble within a multipart/form-data request to trigger this issue. The impact is related to request sizes and concurrency, potentially causing worker crashes or slowdowns due to garbage collection.
**Recommendations**
Update to Rack version 2.2.19 or later.
Update to Rack version 3.1.17 or later.
Update to Rack version 3.2.2 or later.
As a workaround, limit the total request body size at the proxy or web server level.
As a workaround, monitor memory usage and set per-process limits to prevent out-of-memory conditions.