Advisory Weakness Curation

HTTP Response Splitting (Early Hints) in Puma ### Impact If an application using Puma allows untrusted input in an early-hints header, an attacker can use a carriage return character to end the header and inject malicious content, such as additional headers or an entirely new response body. This vulnerability is known as HTTP Response Splitting https://owasp.org/www-community/attacks/HTTP_Response_Splitting. While not an attack in itself, response splitting is a vector for several other attacks, such as cross-site scripting (XSS). This is related to CVE-2020-5247 https://github.com/puma/puma/security/advisories/GHSA-84j7-475p-hp8v, which fixed this vulnerability but only for regular responses. ### Patches This has been fixed in 4.3.3 and 3.12.4. ### Workarounds Users can not allow untrusted/user input in the Early Hints response header. ### For more information If you have any questions or comments about this advisory: * Open an issue in puma https://github.com/puma/puma * Email us a project maintainer. Email addresses are listed in our Code of Conduct https://github.com/puma/puma/blob/master/CODE_OF_CONDUCT.md#enforcement.

Injection Vulnerability In Puma (RubyGem), if an application using Puma allows untrusted input in an early-hints header, an attacker can use a carriage return character to end the header and inject malicious content, such as additional headers or an entirely new response body. This vulnerability is known as HTTP Response Splitting. While not an attack in itself, response splitting is a vector for several other attacks, such as cross-site scripting (XSS).

Injection Vulnerability In Puma (RubyGem), if an application using Puma allows untrusted input in an early-hints header, an attacker can use a carriage return character to end the header and inject malicious content, such as additional headers or an entirely new response body. This vulnerability is known as HTTP Response Splitting. While not an attack in itself, response splitting is a vector for several other attacks, such as cross-site scripting (XSS).