reversemedium

A Simple Stack VM?

hackerlab

Task: a stripped Linux ELF implements a custom stack-based VM that validates a flag through embedded bytecode and a hidden target table. Solution: recover the opcode meanings from the interpreter, isolate the per-byte transform, invert it, and decode the full CODEBY flag offline.

$ ls tags/ techniques/
piebytecodecustom_vmstripped_binarylinux_elfstack_machine
vm_bytecode_analysisopcode_recoverytransform_inversion
🔒

Permission denied (requires tier.pro)

Sign in to access full writeups

Create a free account with GitHub to get started.

$ssh [email protected]