An instance where two different pieces of data are hashed separately, but both result in a single identical hash value is described by what term?

The scenario described, where two distinct pieces of data produce the same hash value when processed through a hash function, is known as a collision. A collision occurs in hashing algorithms when different inputs yield the same output, which undermines the fundamental property of hash functions that ensures unique outputs for unique inputs. This property is critical for integrity checks, digital signatures, and many security protocols where data authenticity and integrity must be maintained.

Hash functions are designed to minimize the chances of a collision, but as data and computing power increase, finding such collisions becomes a concern, especially for older or less robust hashing algorithms. The security implications of collisions are significant, as an attacker could potentially substitute one piece of data for another without detection if they can produce an identical hash, leading to a breach of trust in the hashing mechanism.

The other terms provided do not accurately represent this concept. Duplicate refers to identical data rather than a hashing phenomenon, hashing error implies a malfunction in the hashing process itself, and cryptographic flaw suggests a broader security vulnerability rather than the specific incident of two inputs leading to the same hash output.