The code that performs password matching when using 'Basic' HTTP authentication does not use a constant-time memcmp and has no rate-limiting. This means that an unauthenticated network attacker can brute-force the HTTP basic password, byte-by-byte, by recording the webserver's response time until the unauthorized (401) response.

An issue was discovered in GoAhead 4.x and 5.x before 5.1.5. In the file upload filter, user form variables can be passed to CGI scripts without being prefixed with the CGI prefix. This permits tunneling untrusted environment variables into vulnerable CGI scripts.