CVE-2022-24790: 
Ruby vulnerability analysis and mitigation

CVE-2022-24790 affects Puma, a simple, fast, multi-threaded HTTP 1.1 server for Ruby/Rack applications. The vulnerability was discovered and disclosed on March 30, 2022. The issue affects Puma versions up to 5.6.2 and 4.3.11, with fixes available in versions 5.6.4 and 4.3.12 (GitHub Advisory).

The vulnerability occurs when using Puma behind a proxy that does not properly validate incoming HTTP requests against the RFC7230 standard. This can lead to disagreements between Puma and the frontend proxy about where requests start and end. The vulnerability involves several parsing issues: lenient parsing of Transfer-Encoding headers, malformed Content-Length headers, duplicate Content-Length headers, and improper validation of chunked segment endings. The issue has been assigned a CVSS v3.1 base score of 7.5 HIGH by NIST NVD, while GitHub rates it as 9.1 CRITICAL (NVD).

This vulnerability could allow attackers to perform HTTP request smuggling attacks through the front-end proxy to Puma. When successfully exploited, an attacker could smuggle requests through a proxy, potentially causing the proxy to send responses to unintended clients, leading to security implications such as request forgery or response queue poisoning (GitHub Advisory).

The primary mitigation is to upgrade to Puma versions 5.6.4 or 4.3.12 which contain the security fixes. For users unable to upgrade immediately, a workaround is available by ensuring the front-end proxy strictly validates requests against the RFC7230 standard. Several proxy servers are known to have proper validation behavior, including latest versions of Nginx, Apache, Haproxy 2.5+, Caddy, and Traefik (GitHub Advisory).