55. A network security analyst monitors the network's IDS, which has flagged unusual activity. The IDS has detected multiple login attempts to a database server within a short period. These attempts come from various IP addresses that are not normally recognized by the network's usual traffic patterns. Each attempt uses the same username and password. Which of the following types of network attacks is most likely occurring?
Answer: B
Credential replay is most likely occurring.
The unusual activity flagged by the IDS, characterized by multiple login attempts from various unrecognized IP addresses using the same username and password, indicates a credential replay attack. This type of attack involves reusing valid credentials to gain unauthorized access.
A) Cross-site scripting
Cross-site scripting (XSS) is a type of attack where malicious scripts are injected into trusted websites. It primarily targets users rather than attempting to gain unauthorized access to a server or system. Given that the scenario describes repeated login attempts rather than script injection or user exploitation, this option is incorrect.
B) Credential replay
Credential replay involves the reuse of valid username and password combinations to access a system, often observed through multiple login attempts from various IP addresses. In this scenario, the consistent use of the same credentials from different sources strongly indicates that a credential replay attack is taking place.
C) Distributed denial of service
A distributed denial of service (DDoS) attack aims to overwhelm a service with traffic, rendering it unavailable. The situation described does not involve an attempt to disrupt service but rather focuses on unauthorized access through repeated logins. Therefore, this option is not applicable.
D) SQL injection
SQL injection is an attack method that involves injecting malicious SQL queries into input fields to manipulate database operations. The current scenario does not involve executing SQL commands or manipulating database queries, making this option incorrect.
Conclusion
Credential replay attacks are characterized by the reuse of valid login credentials from various sources, as seen in this scenario. The other options do not align with the described activity, which emphasizes unauthorized access attempts rather than service disruption or code injection. Thus, option B is the definitive choice for the type of attack occurring.