On the Randomness Timing Analysis of Timing Side Channel Attack on Key Derivation Functions

Robust security framework with bit‐flipping attack and timing attack for key derivation functions

“…According to the paper published by Koh and Chuah [28], the practical approach of introducing the randomness timing to the KDF can help to mitigate the timing side‐channel attack on KDFs. Hence, this paper introduces theoretical randomness timing to the KDF7 for mitigating the timing attack.…”

“…Definition 11 (KDF with randomness timing) : A randomness timing is used to mitigate the timing attack on KDF [28]. The randomness timing can mask the actual execution time used by KDF to generate the derived cryptographic key.…”

“…The design of KDF7 will include the randomness timing as defined in Definition 11 to mitigate the timing attack [28]. Besides that, the underlying cryptographic primitives used to construct the extractor and expander can be the SHA‐based HMAC [25] or AES‐CMAC [26].…”

“…Hence, A does not know which cryptographic primitives, such as a hash function or block cipher is used to construct the KDF7. Based on the paper published by Koh and Chuah [28], the practical approach of introducing the randomness timing to KDF can help to mitigate the timing side‐channel attack on KDFs. The result showed that randomness timing introduced to KDF caused the actual execution time output by KDF to be randomised.…”

“…Thus, there is a trade‐off between the security and performance efficiency. The theoretical randomness timing is possible to be introduced in KDF7 with this instantiation [28] for protecting the security of KDF7. Thus, KDF7 is theoretically secure in CAM‐TA because A cannot use the randomness timing to distinguish the challenge output as well as determine the underlying cryptographic primitive used to construct KDF7.…”