Attacking a stack based JavaScript virtual machine
a day ago
- The research analyzes three JavaScript obfuscators, focusing on PixelMelt's PISTOL virtual machine obfuscation.
- The first challenge (1.0.js) was solved by finding the flag directly in the constant pool after base64 decoding.
- The second challenge (2.o.js) involved reversing a rolling XOR cipher by inspecting the VM stack and tracing operations.
- The third challenge (3.o.js) required building a tracer to understand an RC4-like cipher, but an AI-generated trace corrupted a byte, causing a near-miss solution.
- Key lessons include the importance of validating tool outputs and the value of simple attack vectors before complex analysis.