CVE-2021-4034 PoC — polkit 缓冲区错误漏洞

Source

https://github.com/CYB3RK1D/CVE-2021-4034-POC

Associated Vulnerability

Title:polkit 缓冲区错误漏洞 (CVE-2021-4034)
Description:A local privilege escalation vulnerability was found on polkit's pkexec utility. The pkexec application is a setuid tool designed to allow unprivileged users to run commands as privileged users according predefined policies. The current version of pkexec doesn't handle the calling parameters count correctly and ends trying to execute environment variables as commands. An attacker can leverage this by crafting environment variables in such a way it'll induce pkexec to execute arbitrary code. When successfully executed the attack can cause a local privilege escalation given unprivileged users administrative rights on the target machine.

Description

pwnkit

Readme

### CREDITS
 VULNERABILITY AUTHOR: https://blog.qualys.com/vulnerabilities-threat-research/2022/01/25/pwnkit-local-privilege-escalation-vulnerability-discovered-in-polkits-pkexec-cve-2021-4034
 
 # Reference 
 https://github.com/arthepsy/CVE-2021-4034/blob/main/cve-2021-4034-poc.c
 
 https://linux.die.net/man/1/pkexec
 
 
 man_page/pkexec:
 
  
       Note that pkexec does no validation of the ARGUMENTS passed to PROGRAM.
       In the normal case (where administrator authentication is required
       every time pkexec is used), this is not a problem since if the user is
       an administrator he might as well just run pkexec bash to get root.

       However, if an action is used for which the user can retain
       authorization (or if the user is implicitly authorized), such as with
       pk-example-frobnicate above, this could be a security hole. Therefore,
       as a rule of thumb, programs for which the default required
       authorization is changed, should never implicitly trust user input
       (e.g. like any other well-written suid program).      
  
 by the author David Zeuthen <davidz@redhat.com>
  written in may 2009.
 # GCONV resources
 https://www.gnu.org/software/libc/manual/html_node/glibc-iconv-Implementation.html#:~:text=for%20all%20conversions.-,gconv,use%20of%20the%20conversion%20functions.
 https://hugeh0ge.github.io/2019/11/04/Getting-Arbitrary-Code-Execution-from-fopen-s-2nd-Argument/
 
 

# PwnFunction
  
  EXPLANATION VIDEO: https://youtu.be/eTcVLqKpZJc
 

# TO DO
   Port the exploit to rust
   
   need to write an explanation for exploit

File Snapshot


 [4.0K]  /data/pocs/ce94d59d5e456dffc87a5dc895eafe3c67c023c8
├── [1.2K]  pkexec_exploit.c
├── [  53]  pkexec_exploit.rs
└── [1.6K]  README.md

0 directories, 3 files

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