0x03arm32hackingfloat

November 27, 2025 · View on GitHub

FREE Reverse Engineering Self-Study Course HERE

ARM 32-bit Raspberry Pi Hacking Float example in Kali Linux.

POWER UP DEVICE AND LOGIN AS KALI AND SET UP SSH

#include <stdio.h>

int main()
{
    float x;

    x = 10.5;

    printf("%0.2f\n", x);

    return 0;
}

gcc -o 0x03_arm_32_hacking_float 0x03_arm_32_hacking_float.c

./0x03_arm_32_hacking_float
10.50

r2 -d ./0x03_arm_32_hacking_float

aaa
s main
vv

q
[0x0046550c]> pd 2 @ 0x00465512
│           0x00465512      4ff00003       mov.w r3, 0
│           0x00465516      c4f22813       movt r3, 0x4128

wa movw r3, 0xd70a @0x00465512
wa movt r3, 0x4127 @0x00465516

[0x0046550c]> pd 2 @ 0x00465512
│           0x00465512      4df20a73       movw r3, 0xd70a
│           0x00465516      c4f22713       movt r3, 0x4127

q
r2 -w ./0x03_arm_32_hacking_float
[0x000003fc]> aaa
[0x000003fc]> s main
[0x0000050c]> vv

q
[0x0000050c]> wa movw r3, 0xd70a @0x00000512
[0x0000050c]> wa movt r3, 0x4127 @0x00000516

./0x03_arm_32_hacking_float
10.49

** NOTE ** If you wanted to hack from 10.50 to 10.51 instead you would simply:

[0x0000050c]> wa movw r3, 0x28f6 @0x00000512
[0x0000050c]> wa movt r3, 0x4128 @0x00000516

This should give you a good idea how the LSB and MSB work for floating point numbers now.