The correct action is to modify the SSH configuration to disable weak ciphers and enable strong ciphers, as this directly addresses the cryptographic vulnerabilities identified in the scan. Weak ciphers such as CBC-mode encryption or MD5-based MACs are susceptible to attacks like plaintext recovery or hash collision, so the remediation must involve editing the sshd_config file to enforce strong algorithms like AES-CTR or ChaCha20-Poly1305. On the CISSP exam, this scenario tests your understanding of cryptographic protocol hardening within the Communication and Network Security domain, where a common trap is assuming that simply upgrading the SSH service version will automatically update the cipher list—it will not, as the cipher configuration is independent of the software version. Remember, the goal is to disable weak ciphers, not to disable the service or hide the vulnerability. Memory tip: think “Cipher Lock” – you must lock out weak ciphers by explicitly configuring strong ones in the config file.
CISSP Security Assessment and Testing Practice Question
This CISSP practice question tests your understanding of security assessment and testing. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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.
Exhibit
Refer to the exhibit.
```
[Vulnerability Scan Report - Snippet]
Host: 10.0.0.15
Port: 22/tcp
Service: SSH
Vulnerability: Weak SSH Cryptographic Algorithms
Severity: Medium
CVE: CVE-2016-0777
Fix: Disable weak ciphers (arcfour, blowfish-cbc) and enable strong ones (aes256-ctr, aes128-ctr)
```
Exhibit:
A system administrator receives the vulnerability scan report snippet shown in the exhibit. Which of the following actions should the administrator take to remediate the vulnerability?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Modify the SSH configuration to disable weak ciphers and enable strong ciphers.
The vulnerability scan report likely identifies weak cryptographic algorithms (e.g., CBC-mode ciphers or MD5-based MACs) in the SSH configuration. Remediation requires disabling these weak ciphers and enabling strong ones (e.g., AES-CTR, ChaCha20-Poly1305) in the sshd_config file, as simply upgrading the SSH service version may not change the cipher list. Option B directly addresses the cryptographic weakness without unnecessarily disabling or hiding the service.
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.
✗
Upgrade the SSH service to the latest version.
Why it's wrong here
Upgrading may not change the cipher configuration; it must be explicitly set.
✓
Modify the SSH configuration to disable weak ciphers and enable strong ciphers.
Why this is correct
This directly addresses the vulnerability as recommended in the report.
Related concept
Read the scenario before looking for a memorised answer.
✗
Disable SSH access to the host.
Why it's wrong here
Disabling SSH is too extreme and may impact legitimate access.
✗
Change the SSH port from 22 to a non-standard port.
Why it's wrong here
Changing the port does not fix the weak cipher vulnerability.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume upgrading the software version automatically fixes all vulnerabilities, but CISSP tests the understanding that configuration hardening (e.g., disabling weak ciphers) is a separate and necessary action even after a version upgrade.
Detailed technical explanation
How to think about this question
SSH cipher negotiation occurs during the key exchange phase, where the client and server agree on a mutually supported cipher from the server's configured list. Weak ciphers like arcfour, blowfish-cbc, or 3des-cbc are vulnerable to attacks such as plaintext recovery or bit-flipping, and disabling them is enforced via the 'Ciphers' directive in sshd_config. In real-world scenarios, compliance frameworks like PCI DSS require strong cryptography (e.g., AES-128-CTR or higher) for all administrative access, making cipher hardening a critical step.
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 CISSP question in full detail.
Security Assessment and Testing — This question tests Security Assessment and Testing — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Modify the SSH configuration to disable weak ciphers and enable strong ciphers. — The vulnerability scan report likely identifies weak cryptographic algorithms (e.g., CBC-mode ciphers or MD5-based MACs) in the SSH configuration. Remediation requires disabling these weak ciphers and enabling strong ones (e.g., AES-CTR, ChaCha20-Poly1305) in the sshd_config file, as simply upgrading the SSH service version may not change the cipher list. Option B directly addresses the cryptographic weakness without unnecessarily disabling or hiding the service.
What should I do if I get this CISSP question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 CISSP practice question is part of Courseiva's free ISC2 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 CISSP 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.