Tag: CTF

All the articles with the tag "CTF".

• Christmas CTF 2019 / Christmas Pocket

  27 Dec, 2019

  Christmas CTF 2019 Christmas Pocket write-up — recovering the private key of a knapsack-based public-key scheme by working through the key-generation math.

• X-MAS CTF 2018 / Santa's List

  23 Dec, 2019

  X-MAS CTF 2018 Santa's List write-up — an RSA chosen-ciphertext attack (CCA) that slips past the decryption filter to recover the flag.

• DEF CON 2019 Quals / RTOoOS

  8 Jul, 2019

  DEF CON 2019 Quals RTOoOS write-up — reversing a custom shell binary that runs on a macOS hypervisor, then abusing malloc's NULL return to plant shellcode at address 0 and bypass the hypercall filter.