CVE-2025-49007

A flaw was found in Rack. The Content-Disposition parsing component exhibits a denial of service vulnerability due to improper handling of specially crafted input, allowing a remote attacker to trigger a crash. This vulnerability is triggered by processing a malicious Content-Disposition header. Consequently, a remote attacker can cause the Rack web server interface to become unavailable.

This vulnerability in Rack is considered Important rather than Moderate due to its impact on core request handling and application availability. The flaw lies in the inefficient parsing of the Content-Disposition header, commonly used in multipart form submissions. An attacker can exploit this by sending specially crafted input that causes the parser to consume excessive CPU resources, leading to a denial-of-service (DoS) condition. Since virtually all Rails applications and many other Ruby web apps rely on Rack for multipart parsing, the attack surface is widespread and affects production systems at the framework level. The attack does not require authentication and can be triggered with a single malicious request, making it low-cost but high-impact. Furthermore, because the vulnerability is exploited during early request processing, it can bypass typical application-level protections. This combination of broad exposure, low complexity, and high disruption potential elevates the severity to important.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.