Kallithea suffers from a HTTP header injection (response splitting) vulnerability because it fails to properly sanitize user input before using it as an HTTP header value via the GET ‘came_from’ parameter in the login instance. This type of attack not only allows a malicious user to control the remaining headers and body of the response the application intends to send, but also allow them to create additional responses entirely under their control. Versions 0.2.9 and 0.2.2 are affected.