The answer is ransomware, as this malware is specifically designed to encrypt files and demand payment for decryption. When a file server suddenly renames documents with a new extension, it indicates that ransomware has appended a custom marker to each encrypted file, a technical hallmark of its encryption process. The subsequent ransom note demanding cryptocurrency confirms the extortion motive, distinguishing ransomware from other malware like worms or trojans that lack this financial coercion. On the Security+ SY0-701 exam, this scenario tests your ability to recognize ransomware’s dual signature: file renaming plus a ransom demand. A common trap is confusing ransomware with a logic bomb, but remember that only ransomware actively seeks payment to reverse encryption. For a quick memory tip, think “REName + Ransom = Ransomware,” linking the renamed files to the extortion note.
SY0-701 Threats, Vulnerabilities, and Mitigations Practice Question
This SY0-701 practice question tests your understanding of threats, vulnerabilities, and mitigations. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A file server suddenly renames documents with a new extension and displays a note demanding payment in cryptocurrency to restore access. What type of malware is most likely involved?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
This is the classic symptom pattern for ransomware. Files are renamed or encrypted, access is disrupted, and the attacker demands payment for recovery. The ransom note and the sudden file changes together make ransomware the best answer.
B
Spyware
Why wrong: Spyware hides activity and collects information without the user's knowledge. It usually does not encrypt files or demand payment for recovery.
C
Worm
Why wrong: A worm spreads across systems on its own, but the key symptom here is file encryption and ransom behavior, not network self-replication.
D
Rootkit
Why wrong: A rootkit is intended to conceal malicious access and processes. It does not usually rename files and demand cryptocurrency for unlocking them.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Ransomware
Ransomware is designed to encrypt files on a system, making them inaccessible, and then demand a ransom—typically in cryptocurrency—to restore access. The sudden renaming of documents with a new extension is a hallmark of ransomware encryption, as it appends a custom extension to indicate the files have been locked. The displayed note demanding payment confirms the extortion motive, which is unique to ransomware among the given options.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
Ransomware
Why this is correct
This is the classic symptom pattern for ransomware. Files are renamed or encrypted, access is disrupted, and the attacker demands payment for recovery. The ransom note and the sudden file changes together make ransomware the best answer.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
Spyware
Why it's wrong here
Spyware hides activity and collects information without the user's knowledge. It usually does not encrypt files or demand payment for recovery.
✗
Worm
Why it's wrong here
A worm spreads across systems on its own, but the key symptom here is file encryption and ransom behavior, not network self-replication.
✗
Rootkit
Why it's wrong here
A rootkit is intended to conceal malicious access and processes. It does not usually rename files and demand cryptocurrency for unlocking them.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates may confuse ransomware with other malware types that alter files or display messages, but only ransomware specifically encrypts files and demands a ransom for decryption.
Detailed technical explanation
How to think about this question
Ransomware typically uses symmetric encryption (e.g., AES-256) to encrypt files quickly, then encrypts the symmetric key with an asymmetric public key (e.g., RSA-2048) so only the attacker can decrypt. The new file extension is often a random string or the attacker's identifier, and the ransom note is usually placed as a text file (e.g., 'README.txt') in every directory. In real-world attacks like WannaCry, the malware exploited SMBv1 vulnerabilities (EternalBlue) to spread and encrypt files, demanding Bitcoin payments.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A developer is choosing between AES-256 (symmetric) and RSA-2048 (asymmetric) for encrypting a large file that will be sent to a partner. Symmetric encryption is fast but requires key exchange; asymmetric is slower but solves the key distribution problem. A hybrid approach — encrypt the file with AES, encrypt the AES key with RSA — is standard. Questions like this test whether you understand when each approach applies.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this SY0-701 question in full detail.
Threats, Vulnerabilities, and Mitigations — This question tests Threats, Vulnerabilities, and Mitigations — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Ransomware — Ransomware is designed to encrypt files on a system, making them inaccessible, and then demand a ransom—typically in cryptocurrency—to restore access. The sudden renaming of documents with a new extension is a hallmark of ransomware encryption, as it appends a custom extension to indicate the files have been locked. The displayed note demanding payment confirms the extortion motive, which is unique to ransomware among the given options.
What should I do if I get this SY0-701 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This SY0-701 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 SY0-701 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.