An issue was discovered in Overhang.IO (tutor-open-edx) (overhangio/tutor) 20.0.2 allowing local unauthorized attackers to gain access to sensitive information due to the absence of proper cache-control HTTP headers and client-side session checks.
Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.
Such a scenario is commonly observed when:
In the generic exploit of session fixation vulnerabilities, an attacker creates a new session on a web application and records the associated session identifier. The attacker then causes the victim to associate, and possibly authenticate, against the server using that session identifier, giving the attacker access to the user’s account through the active session.