CVE-2021-4034 PoC — polkit 缓冲区错误漏洞

Source

https://github.com/mutur4/CVE-2021-4034

Associated Vulnerability

Title:polkit 缓冲区错误漏洞 (CVE-2021-4034)
Description:polkit是一个在类 Unix操作系统中控制系统范围权限的组件。通过定义和审核权限规则，实现不同优先级进程间的通讯。 polkit 的 pkexec application存在缓冲区错误漏洞，攻击者可利用该漏洞通过精心设计环境变量诱导pkexec执行任意代码。成功执行攻击后，如果目标计算机上没有权限的用户拥有管理权限，攻击可能会导致本地权限升级。

Readme

# CVE-2021-4034

This is a PoC for PwnKit __*Local Privilege Escalation Vulnerability*__ 
that was discovered by [Qualys Security Team](https://blog.qualys.com/vulnerabilities-threat-research/2022/01/25/pwnkit-local-privilege-escalation-vulnerability-discovered-in-polkits-pkexec-cve-2021-4034).

>The Qualys Research Team has discovered a memory corruption vulnerability in polkit’s pkexec, a SUID-root program that is installed by default on every major Linux distribution.

#### Proof Of Concept

*The following image is used to show the payload in action in a debian based operating system*

![poc.png](https://i.imgur.com/V5I8SBf.png)

#### Usage

- There are two POCs provided a self-contained that does not require any dependencies installed in the vulnerable endpoint i.e GCC.

#### Recommendations 
- The immediate recommendation was to remove the `SUID` bit of the polkit binary/executable.

File Snapshot


 [4.0K]  /data/pocs/2d2096eadc0c07771e2a74dfec24a145a16379a7
├── [ 281]  Makefile
├── [ 18K]  pwnkit
├── [4.5K]  pwnkit.c
├── [ 904]  README.md
└── [4.0K]  self-contained-version
    ├── [2.6K]  pwnkit.c
    └── [ 362]  README.md

1 directory, 6 files

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