PoC for cve-2021-4034# cve-2021-4034
PoC for cve-2021-4034
Based on the PoC by https://haxx.in: https://haxx.in/files/blasty-vs-pkexec.c. Probably he's https://github.com/blasty?! I don't know.
With a little help from https://github.com/daimoniac
# How to use?
## Compile cve-2021-4034.c
```
gcc -Wall cve-2021-4034.c -o cve-2021-4034-exploit
```
## Execute ansible playbook
**Change variable `hosts` in `asses_CVE-2021-4034.yml` to your usecase!**
```
ansible-playbook -i </path/to/inventory.yml> </path/to/playbooks/>asses_CVE-2021-4034.yml
```
The playbook copies the exploit to the host, executes it and evaluates `whoami` on multiple occasions and checks for "root" as return value of the exploit.
On hosts where the task `Check result of privilege escalation` fails a privilge escalation was successful.
In the play recap hosts which don't have `failed=0` are vulnerable.
# What does it do?
Deep down? I have no idea. Weired memory mashups probably.
What's essential for the operability of this anbible playbook is https://github.com/mike-artemis/cve-2021-4034/blob/main/cve-2021-4034.c#L50. The plain exploit by https://haxx.in/files/blasty-vs-pkexec.c only opens a root-shell and the ansible playbook is stuck in it.
Changing the payload of the exploit to
```
" static char *a_argv[] = { \"bash\", \"-c\", \"whoami\", NULL };\n"
```
return the current user. The playbook checks the user for privilege escalation and fails the playbook if it happened.
[4.0K] /data/pocs/5f9d3580cfe755ee6dfdfb3b28628053e6785c2f
├── [1.4K] asses_CVE-2021-4034.yml
├── [2.3K] cve-2021-4034.c
└── [1.4K] README.md
0 directories, 3 files