Quiz Entry - updated: 2026.07.14
What are the 8 attacks in the classic cryptographic communication model?
There are 8 fundamental attacks: eavesdropping, modifying, inserting, replaying, deleting messages, plus denying sending, denying receiving, and masquerading as someone else.
* The classic Alice / Eve / Bob model: 5 channel attacks, 2 repudiation attacks, 1 identity attack. *
The attacks target a channel between sender Alice (A) and receiver Bob (B), with attacker Eve (E):
| # | Attack | Target |
|---|---|---|
| 1 | Eavesdropping (Abhören) | Confidentiality |
| 2 | Modifying (Verändern) | Data integrity |
| 3 | Inserting (Einfügen) | Data authenticity |
| 4 | Replaying (Wiedereinspielen) | Freshness |
| 5 | Deleting (Löschen/Unterdrücken) | Availability |
| 6 | Non-repudiation of origin (Abstreiten Senden) | Accountability of sender |
| 7 | Non-repudiation of receipt (Abstreiten Empfang) | Accountability of receiver |
| 8 | Masquerade (Vortäuschen Identität) | User authenticity |
Tip: Group them as: 5 channel attacks (1-5), 2 repudiation attacks (6-7), 1 identity attack (8).
Go deeper:
Information security (CIA triad) — the confidentiality/integrity/availability goals these attacks target.