Access abuse is the misuse of valid credentials, session cookies, API tokens, or other legitimate authentication material to perform actions the owner did not intend. Unlike a classic intrusion that breaks in through a software flaw, access abuse often looks like normal sign-in traffic because the attacker is using real access paths.
This matters because defenders may not see obvious malware or exploit activity, yet accounts can still be used to stream, steal data, resell services, or move laterally inside a network. In real attacks, stolen passwords, reused session tokens, and shared authentication codes can let criminals act as trusted users until the session is revoked or the account is flagged. Common defenses include multi-factor authentication, short-lived tokens, rate limits, anomaly detection, device and IP monitoring, and fast revocation of suspicious sessions. The key idea is to protect not just the password, but every reusable piece of access.