The escape_dangerous_chars function in CGI::Lite 2.0 and earlier does not correctly remove special characters including (1) "\" (backslash), (2) "?", (3) "~" (tilde), (4) "^" (carat), (5) newline, or (6) carriage return, which could allow remote attackers to read or write arbitrary files, or execute arbitrary commands, in shell scripts that rely on CGI::Lite to filter such dangerous inputs.