CAS-004 Security Operations Practice Question
A security analyst is reviewing logs from a SIEM and notices that a user account has been successfully authenticated from two different geographic locations within a short time span, which is impossible. The SIEM uses user behavior analytics (UBA). What type of anomaly is this most likely to detect?
⚠ Common exam trap
CAS-005 often tests the distinction between anomaly types, and candidates may confuse brute-force attacks (which involve multiple failed logins) with credential theft (successful logins from impossible locations), or they may overlook that the scenario specifies successful authentication, leading them to choose brute-force or MITM.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
A credential theft and reuse incident
The scenario describes a successful authentication from two geographically distant locations within a time span that makes physical travel impossible. This is a classic indicator of credential theft and reuse, where an attacker has obtained valid credentials and is using them from a different location while the legitimate user is also active. UBA detects this as an anomaly because it deviates from the normal access pattern for that user, such as typical login locations and times.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
A credential theft and reuse incident
Why this is correct
Impossible travel is the classic UBA signal: the same credentials authenticating from two distant locations faster than physical travel allows. This pattern indicates the account's credentials have been compromised and reused by an attacker, directly matching the impossible-login constraint described in the stem.
- ✗
A misconfigured VPN that routes traffic through multiple gateways
Why it's wrong here
VPN misconfiguration might cause different source IPs, but not necessarily impossible travel times.
- ✗
A brute-force attack on the user account
Why it's wrong here
Brute-force would show multiple failed logins, not successful logins from distant locations.
- ✗
A man-in-the-middle attack intercepting the authentication
Why it's wrong here
MITM attacks would not necessarily cause logins from different locations.
Go deeper
Related to this question
About these practice questions
This CAS-005 question is part of Courseiva's 973-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official CompTIA exam blueprint
This CAS-005 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CAS-005 exam.