Question 100
During an application modernization project at Atlas Scientific, engineers say that they resolved this finding: A file integrity workflow uses reversible encryption as its only proof that a downloaded update was unmodified. Which result provides the STRONGEST acceptance evidence?
Explanation
Correct Answer
A tampered update fails signature validation while the authentic package validates. This is the decisive evidence for the original problem: A file integrity workflow uses reversible encryption as its only proof that a downloaded update was unmodified. It verifies that the intended corrective control—Use a cryptographic digest and verified digital signature for integrity and publisher authenticity—works in the relevant environment; a completed change ticket alone would not prove the outcome at Atlas Scientific.
Incorrect Answers
Credential storage contains salted adaptive hashes rather than plaintext or fast unsalted digests. This would be relevant evidence for a different failure: A security team assumes a fast general-purpose hash can safely protect stored user passwords by itself, usually addressed by Use an adaptive password-hashing function with unique salts and suitable work factors. It does not demonstrate that the current problem at Atlas Scientific was resolved. The specific required evidence is: A tampered update fails signature validation while the authentic package validates.
A tunnel behind NAT establishes and carries protected traffic without ESP being dropped. This would be relevant evidence for a different failure: A NAT gateway changes IPsec peer addresses and native ESP traffic fails through the path, usually addressed by Use supported IPsec NAT traversal with UDP encapsulation and matching peer configuration. It does not demonstrate that the current problem at Atlas Scientific was resolved. The specific required evidence is: A tampered update fails signature validation while the authentic package validates.
The negotiated security associations protect bidirectional traffic and are visible in VPN status. This would be relevant evidence for a different failure: Two remote offices require confidentiality and authenticated integrity for traffic traversing the public Internet, usually addressed by Configure standards-based IPsec using appropriate IKE authentication and encryption proposals. It does not demonstrate that the current problem at Atlas Scientific was resolved. The specific required evidence is: A tampered update fails signature validation while the authentic package validates.