Certified Information Security Manager (CISM) — Question 497

A common drawback of email software packages that provide native encryption of messages is that the encryption:

Answer options

• A. has an insufficient key length.
• B. cannot interoperate across product domains.
• C. cannot encrypt attachments.
• D. has no key-recovery mechanism.

Correct answer: B

Explanation

The correct answer is B because many email encryption systems are not compatible with each other, making it difficult to exchange encrypted messages between different software. Option A is incorrect as key lengths can vary and are not universally inadequate. Option C is wrong because many encryption methods can encrypt attachments, and Option D is not universally true since some systems do have key-recovery mechanisms.