I started manually reversing the binary using ghidra, but it seems like a problem that angr should easily be able to automatically solve.

```python
import angr, claripy

proj = angr.Project('high_quality_checks')

arg1 = claripy.BVS('arg1', 20*8)
initial_state = proj.factory.entry_state(args=["high_quality_checks", arg1])

simgr = proj.factory.simulation_manager(initial_state)

# Address 0x400ad2 is found using ghidra (it is the location that prints "You found the flag")
simgr.explore(find=0x400ad2, avoid=[])

print(simgr.found[0].posix.dumps(0)) # actf{fun_func710n5}
```


Original writeup (https://github.com/NicolaiSoeborg/ctf-writeups/blob/master/2019/%C3%85ngstrom%20CTF%202019/high_quality_checks.py).