Packed Writeup
Cyber Apocalypse 2024
solved by : avantika(@iamavu)
we are given a binary, called packed i.e this has been obfuscated/packed by the dev, which hinders our exploitation and reversing as it’s very hard to understand what’s going on
we use checksec command provided by pwntools to check which packer they have used
pwn checksec packed
as we can observe it has been packed with UPX, quite the popular packer, now we just need to unpack it to see all the functions properly, so we can dissect it using the following command
upx -d -o unpacked packed
we would now have binary called unpacked in our current directory, which will be unpacked and not obfuscated
fire up your ghidra, let’s have a look at the functions, the entered
function has our flag in plaintext, so pretty much easy win
HTB{unp4ck3d_th3_s3cr3t_0f_th3_p455w0rd}
pwned!