cryptoPromedium

Cyber

volgactf

Task: Custom Kyber-like Module-LWE encryption with N=80, K=2, q=3329; public key matrix A has a zero sub-block making it triangular. Solution: exploit triangular structure to decompose into independent Ring-LWE instances, solve each via BKZ lattice reduction + Babai CVP, recover encryption randomness, then decrypt.

$ ls tags/ techniques/
numpylatticelllpkcs7fpylllkybermlwering_lwenegacyclic_convolutionbkztriangular_matrix
triangular_matrix_exploitationbkz_lattice_reductionbabai_cvpring_lwe_small_dimensionnegacyclic_convolution_linearization
🔒

Permission denied (requires tier.pro)

Sign in to access full writeups

Sign in with GitHub to continue. No email required.

$sign in

$ grep --similar

Similar writeups