CVE-2023-40175: 
Ruby vulnerability analysis and mitigation

Puma, a Ruby/Rack web server built for parallelism, was found to have a vulnerability (CVE-2023-40175) that allowed HTTP request smuggling attacks. The vulnerability was discovered in versions prior to 6.3.1 and 5.6.7, and was disclosed on August 18, 2023. The issue stemmed from incorrect parsing of chunked transfer encoding bodies and zero-length Content-Length headers (GitHub Advisory).

The vulnerability manifested in two ways: incorrect parsing of trailing fields in chunked transfer encoding bodies and improper handling of blank/zero-length Content-Length headers. The issue received a CVSS 3.1 base score of 9.8 (CRITICAL) from NIST NVD, while GitHub assessed it with a score of 7.3 (HIGH). The vulnerability was classified under CWE-444 (Inconsistent Interpretation of HTTP Requests) (NVD).

The severity of this vulnerability was highly dependent on the nature of the website using Puma. The vulnerability could allow attackers to perform HTTP request smuggling attacks, potentially leading to unauthorized access and security bypasses. The high CVSS scores indicate the potential for significant security impact (Red Hat).

The vulnerability has been fixed in Puma versions 6.3.1 and 5.6.7. Users are advised to upgrade to these patched versions as there are no known workarounds for this vulnerability (GitHub Advisory).