Lin Hsin Hsin Quantum Security Center




Attacks on Post-Quantum Cryptography






    OVERVIEW






    Broken or Weakened Algorithms


    Several post-quantum cryptographic algorithms have been broken or weakened due to advances in mathematical attacks and improved computational power



    Major Attacks Summary







    Year Target Algorithm Attack Method Damage/Result
    2022–2023 Rainbow Algebraic (UOV, Gröbner basis) Practical forgery attacks; withdrawn from NIST
    2022 SIKE GPS attack (torsion point info) Complete break; abandoned
    2010s–2020s NTRU Lattice reduction (BKZ 2.0) Weakened parameters; reduced security
    2000s–2020s Non-McEliece Code-Based Decoding (Stern, ISD) Most broken; only McEliece remains
    1990s GGH Lattice basis reduction (LLL, BKZ) Practical breaks; obsolete

    Wishful Secure Algorithms (as of 2026)



    Key Takeaways


    📍 Multivariate and isogeny-based schemes have seen the most dramatic breaks
    📍 Lattice-based schemes (like ML-KEM/Kyber) remain secure with careful parameter selection
    📍 Code-based schemes are mostly secure only if using Classic McEliece with Goppa codes.


    Data compiled from NIST, academic papers, and cryptographic research (2026)