Paper 2022/1681

Backdooring Post-Quantum Cryptography: Kleptographic Attacks on Lattice-based KEMs

Prasanna Ravi, Nanyang Technological University
Shivam Bhasin, Nanyang Technological University
Anupam Chattopadhyay, Nanyang Technological University
Sujoy Sinha Roy, Graz University of Technology

Post-quantum Cryptography (PQC) has reached the verge of standardization competition, with Kyber as a winning candidate. In this work, we demonstrate practical backdoor insertion in Kyber through kleptrography. The backdoor can be inserted using classical techniques like ECDH or post-quantum Classic Mceliece. The inserted backdoor targets the key generation procedure where generated output public keys subliminally leak information about the secret key to the owner of the backdoor. We demonstrate first practical instantiations of such attack at the protocol level by validating it on TLS 1.3.

Available format(s)
Public-key cryptography
Publication info
Kleptography Lattice-based Cryptography Kyber KEM Post-Quantum Cryptography Backdoor
Contact author(s)
prasanna ravi @ ntu edu sg
sbhasin @ ntu edu sg
anupam @ ntu edu sg
aikata @ iaik tugraz at
sujoy sinharoy @ iaik tugraz at
2022-12-03: revised
2022-12-02: received
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      author = {Prasanna Ravi and Shivam Bhasin and Anupam Chattopadhyay and Aikata and Sujoy Sinha Roy},
      title = {Backdooring Post-Quantum Cryptography: Kleptographic Attacks on Lattice-based KEMs},
      howpublished = {Cryptology ePrint Archive, Paper 2022/1681},
      year = {2022},
      note = {\url{}},
      url = {}
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