A security analyst received an alert from the SIEM indicating numerous login attempts from users outside their usual geographic zones, all of which were initiated through the web-based mail server.
The logs indicate all domain accounts experienced two login attempts during the same time frame.
Which of the following is the MOST likely cause of this issue?
Click on the arrows to vote for the correct answer
A. B. C. D.A.
https://doubleoctopus.com/security-wiki/threats-and-tools/password-spraying/Based on the given scenario, it is most likely that the organization is facing a password-spraying attack. Here's why:
A password-spraying attack is a type of brute-force attack where an attacker attempts to guess the passwords of a large number of users in an organization by trying a few commonly used passwords across many different user accounts. The goal of this attack is to find one or more valid credentials that the attacker can then use to gain unauthorized access to the system.
In this scenario, the SIEM detected numerous login attempts from users outside the usual geographic zones, all initiated through the web-based mail server. The logs indicate that all domain accounts experienced two login attempts during the same time frame. This pattern of behavior is consistent with a password-spraying attack, where the attacker is trying to log in with a few commonly used passwords across many different user accounts. The fact that the login attempts are coming from outside the usual geographic zones suggests that the attackers may be using compromised accounts from other organizations or countries to launch the attack.
On the other hand, a DDoS attack is a type of attack where an attacker floods a network or server with a large number of requests, overwhelming the system and causing it to become unavailable. While a DDoS attack could potentially affect the organization's web-based mail server, it is unlikely to result in login attempts from outside the usual geographic zones.
Option C, "This was normal shift work activity; the SIEM's AI is learning," is unlikely to be the cause of the issue because it does not explain why all domain accounts experienced two login attempts during the same time frame from users outside the usual geographic zones.
Option D, "A credentialed external vulnerability scan was performed," is also unlikely to be the cause of the issue because a vulnerability scan typically involves testing for security vulnerabilities and does not typically involve login attempts. Additionally, a credentialed scan would require valid credentials, which would not be the case in a password-spraying attack.
Therefore, the most likely cause of the issue is a password-spraying attack, and the security analyst should investigate further to confirm this and take appropriate action to mitigate the attack. This could involve blocking the IP addresses of the attackers, implementing stronger password policies, and monitoring the network for further suspicious activity.