Typical severity: High. Likelihood of attack: High. Session sidejacking takes advantage of an unencrypted communication channel between a victim and target system. The attacker sniffs traffic on a network looking for session tokens in unencrypted traffic. Once a session token is captured, the attacker performs malicious actions by using the stolen token with the targeted application to impersonate the victim. This attack is a specific method of session hijacking, which is exploiting a valid session token to gain unauthorized access to a target system or information. Other methods to perform a session hijacking are session fixation, cross-site scripting, or compromising a user or server machine and stealing the session token.
Make sure that HTTPS is used to communicate with the target system. Alternatively, use VPN if possible. It is important to ensure that all communication between the client and the server happens via an encrypted secure channel. | Modify the session token with each transmission and protect it with cryptography. Add the idea of request sequencing that gives the server an ability to detect replay attacks.