Malleability (cryptography)

Malleability is a property of some cryptographic algorithms. An encryption algorithm is "malleable" if it is possible for an adversary to transform a ciphertext into another ciphertext which decrypts to a related plaintext. That is, given an encryption of a plaintext ${\displaystyle m}$, it is possible to generate another ciphertext which decrypts to ${\displaystyle f(m)}$, for a known function ${\displaystyle f()}$, without necessarily knowing or learning ${\displaystyle m}$.

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