diff --git a/README.md b/README.md index 3bab7d0..12c3a22 100644 --- a/README.md +++ b/README.md @@ -17,7 +17,7 @@ So, I decided to try something sneaky by adding a ";" character to my command. I ![image](https://github.com/duality084/CVE-2023-33381-MitraStar-GPT-2741GNAC/assets/7117259/d9c780f9-649e-49a7-bb19-305abff583db) -So, I decided to try something sneaky by adding a ";" character to my command. I executed "cat /etc/passwd" and guess what? The command ran successfully. +I took it a step further and executed the "sed" command to replace the restricted shell entry in the "/etc/passwd" file with a full interactive shell. ![image](https://github.com/duality084/CVE-2023-33381-MitraStar-GPT-2741GNAC/assets/7117259/729a7bf7-118b-4146-a2ec-3de32de9487e) @@ -26,11 +26,15 @@ As clearly illustrated in the image below, the modifications I made have enabled ![image](https://github.com/duality084/CVE-2023-33381-MitraStar-GPT-2741GNAC/assets/7117259/8ee5c6ba-b4c6-4a3f-829a-ebeb5945f18b) ### Root of cause +Since I had complete admin privileges, I couldn't resist delving deeper to uncover the vulnerable component. While inspecting the browser requests, I noticed something interesting. There were two CGI files, "ping.cgi" and "DiagGeneral.cgi", being targeted by the requests. ![image](https://github.com/duality084/CVE-2023-33381-MitraStar-GPT-2741GNAC/assets/7117259/4c9bd5c9-c71b-4d04-b0b1-718195067902) +After grabbing the files, I had some fun with reverse engineering using Ghidra. Here's the interesting part: in the "ping.cgi" file, I noticed that the **PingIPAddr** parameter was being directly taken from user input without any proper sanitization. The **PingIPAddr** parameter grabbed from user input was stored for future use utilizing the **tcapi_set** function. ![image](https://github.com/duality084/CVE-2023-33381-MitraStar-GPT-2741GNAC/assets/7117259/1ce7c0ff-8964-4934-a5a2-1cf96990c20b) +Lastly, in the DiagGeneral.cgi file the PingIPAddr parameter was retrieved using the **tcapi_get** function and then directly used in the **system** function without any sanitization. This flaw creates a command injection vulnerability, enabling unauthorized execution of arbitrary commands on the system. + ![image](https://github.com/duality084/CVE-2023-33381-MitraStar-GPT-2741GNAC/assets/7117259/a02e6faf-adc3-4da9-9efa-abc58f601a4f)