Improper Verification of Cryptographic Signature
Http-signature is a "Reference implementation of Joyent's HTTP Signature Scheme". In versions <=0.9.11, http-signature signs only the header values, but not the header names. This makes http-signature vulnerable to header forgery. Thus, if an attacker can intercept a request, he can swap header names and change the meaning of the request without changing the signature.
CWE-347 - Improper Verification of Cryptographic Signature
A cryptographic protocol is meant to ensure that services are provided in a secure manner. An application with absent or improper verification of cryptographic signatures allows malicious users to feed false messages to valid users or to disclose sensitive data, subverting the goals of the protocol. This can lead to security failures such as false authentication, account hijacking, and privilege escalation.