A session fixation vulnerability exists in 66biolinks v62.0.0 by AltumCode, where the application does not regenerate the session identifier after successful authentication. As a result, the same session cookie value is reused for users logging in from the same browser, allowing an attacker who can set or predict a session ID to potentially hijack an authenticated session.
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.