CVE-2023-33294
CriticalCVSS 9.8Exploitation Probability (EPSS)
Elevated risk56th percentile - higher than 56% of all known CVEs
Summary
An issue was discovered in KaiOS 3.0 before 3.1 related to the /system/bin/tctweb_server binary that exposes a local web server. This server accepts arbitrary Bash commands and executes them as root, posing a serious security risk to the device.
Risk Assessment
This vulnerability allows an attacker to access the list of installed apps, notifications, and downloads, as well as delete local files and modify system properties, potentially rendering the device inoperable.
Recommendation
It is recommended to update the system to version 3.1 or later to eliminate this vulnerability and implement additional security measures, such as restricting access to port 2929.
Original NVD description (English source)
An issue was discovered in KaiOS 3.0 before 3.1. The /system/bin/tctweb_server binary exposes a local web server that responds to GET and POST requests on port 2929. The server accepts arbitrary Bash commands and executes them as root. Because it is not permission or context restricted and returns proper CORS headers, it's accessible to all websites via the browser. At a bare minimum, this allows an attacker to retrieve a list of the user's installed apps, notifications, and downloads. It also allows an attacker to delete local files and modify system properties including the boolean persist.moz.killswitch property (which would render the device inoperable). This vulnerability is partially mitigated by SELinux which prevents reads, writes, or modifications to files or permissions within protected partitions.