An issue was discovered in the WEBrick toolkit through 1.8.1 for Ruby. It allows HTTP request smuggling by providing both a Content-Length header and a Transfer-Encoding header, e.g., "GET /admin HTTP/1.1\r\n" inside of a "POST /user HTTP/1.1\r\n" request. NOTE: the supplier's position is "Webrick should not be used in production."

References

• https://nvd.nist.gov/vuln/detail/CVE-2024-47220
• ruby/webrick#145
• ruby/webrick@d88321d