CVE-2020-5247

CVE-2020-5247 is an HTTP Response Splitting vulnerability affecting Puma (RubyGem) versions prior to 4.3.2 and 3.12.3, as well as related distributions like Debian and Fedora. It allows an attacker to inject malicious content, such as additional headers or a new response body, by including newline characters in untrusted input within a response header. This vulnerability carries a CVSS score of 7.5 (High), indicating a network-based attack with low complexity and a high impact on integrity, though it is not an attack in itself but a vector for others like XSS. There is currently no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage.