CISSP – Cryptography Exam 2026
Questions and Answers
What is the goal of cryptanalysis?
A. To determine the strength of an algorithm
B. To increase the substitution functions in a cryptographic algorithm
C. To decrease the transposition functions in a cryptographic algorithm
D. To determine the permutations used - Correct answer-A. Cryptanalysis is the
process of trying to reverse-engineer a cryptosystem, with the possible goal of
uncovering the key used. Once this key is uncovered, all other messages encrypted
with this key can be accessed. Cryptanalysis is carried out by the white hats to test
the strength of the algorithm.
The frequency of successful brute force attacks has increased because
A. The use of permutations and transpositions in algorithms has increased.
B. As algorithms get stronger, they get less complex, and thus more susceptible to
attacks.
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
,C. Processor speed and power have increased.
D. Key length reduces over time. - Correct answer-C. A brute force attack is
resource-intensive. It tries all values until the correct one is obtained. As computers
have more powerful processors added to them, attackers can carry out more
powerful brute force attacks.
Which of the following is not a property or characteristic of a one-way hash
function?
A. It converts a message of arbitrary length into a value of fixed length.
B. Given the digest value, it should be computationally infeasible to find the
corresponding message.
C. It should be impossible or rare to derive the same digest from two different
messages.
D. It converts a message of fixed length to an arbitrary length value. - Correct
answer-D. A hashing algorithm will take a string of variable length, the message
can be any size, and compute a fixed-length value. The fixed-length value is the
message digest. The MD family creates the fixed-length value of 128 bits, and
SHA creates one of 160 bits.
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
, What would indicate that a message had been modified?
A. The public key has been altered.
B. The private key has been altered.
C. The message digest has been altered.
D. The message has been encrypted properly. - Correct answer-C. Hashing
algorithms generate message digests to detect whether modification has taken
place. The sender and receiver independently generate their own digests, and the
receiver compares these values. If they differ, the receiver knows
the message has been altered.
Which of the following is a U.S. federal government algorithm developed for
creating secure message digests?
A. Data Encryption Algorithm
B. Digital Signature Standard
C. Secure Hash Algorithm
D. Data Signature Algorithm - Correct answer-C. SHA was created to generate
secure message digests. Digital Signature Standard (DSS) is the standard to create
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
Questions and Answers
What is the goal of cryptanalysis?
A. To determine the strength of an algorithm
B. To increase the substitution functions in a cryptographic algorithm
C. To decrease the transposition functions in a cryptographic algorithm
D. To determine the permutations used - Correct answer-A. Cryptanalysis is the
process of trying to reverse-engineer a cryptosystem, with the possible goal of
uncovering the key used. Once this key is uncovered, all other messages encrypted
with this key can be accessed. Cryptanalysis is carried out by the white hats to test
the strength of the algorithm.
The frequency of successful brute force attacks has increased because
A. The use of permutations and transpositions in algorithms has increased.
B. As algorithms get stronger, they get less complex, and thus more susceptible to
attacks.
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
,C. Processor speed and power have increased.
D. Key length reduces over time. - Correct answer-C. A brute force attack is
resource-intensive. It tries all values until the correct one is obtained. As computers
have more powerful processors added to them, attackers can carry out more
powerful brute force attacks.
Which of the following is not a property or characteristic of a one-way hash
function?
A. It converts a message of arbitrary length into a value of fixed length.
B. Given the digest value, it should be computationally infeasible to find the
corresponding message.
C. It should be impossible or rare to derive the same digest from two different
messages.
D. It converts a message of fixed length to an arbitrary length value. - Correct
answer-D. A hashing algorithm will take a string of variable length, the message
can be any size, and compute a fixed-length value. The fixed-length value is the
message digest. The MD family creates the fixed-length value of 128 bits, and
SHA creates one of 160 bits.
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
, What would indicate that a message had been modified?
A. The public key has been altered.
B. The private key has been altered.
C. The message digest has been altered.
D. The message has been encrypted properly. - Correct answer-C. Hashing
algorithms generate message digests to detect whether modification has taken
place. The sender and receiver independently generate their own digests, and the
receiver compares these values. If they differ, the receiver knows
the message has been altered.
Which of the following is a U.S. federal government algorithm developed for
creating secure message digests?
A. Data Encryption Algorithm
B. Digital Signature Standard
C. Secure Hash Algorithm
D. Data Signature Algorithm - Correct answer-C. SHA was created to generate
secure message digests. Digital Signature Standard (DSS) is the standard to create
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
