Replay or Something Else?

About this interactive

What you are doing: deciding whether each finding is a replay attack. In a replay attack the attacker captures traffic, such as a login exchange, a session token or a request, and sends it again. The attacker does not need to read or change it. That is why hashing or encrypting a credential is not enough on its own: if the protocol accepts the same message twice, the captured copy works. Protocols stop replay with something that changes every time, such as a timestamp, a one-time value or a session that expires. How to use it: ask whether captured traffic was sent again unchanged. Guessing, cracking, reading, altering and flooding are other attacks.

What you'll learn

Recognize a replay attack, where captured traffic or credentials are sent again unchanged to gain access, and tell it apart from other attacks on the same traffic

Aligned to

CompTIA Security+

2.4 Given a scenario, analyze indicators of malicious activity.

Key terms

Replay Attack: An attack in which a threat actor captures valid network data — such as an authentication token or session credential — and retransmits it later to impersonate the original user or device without needing to know the underlying password.
Credential Replay: A type of replay attack in which intercepted authentication data, such as a hashed password, is retransmitted to a server to gain unauthorized access without knowing the original credential.
Man-in-the-Middle Attack: An attack where an adversary secretly intercepts and potentially alters communications between two parties.

Topics

Replay Attack Credential Replay Interactive Streak Sort

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