module

Klog Server authenticate.php user Unauthenticated Command Injection

Disclosed
Dec 27, 2020

Description

This module exploits an unauthenticated command injection vulnerability
in Klog Server versions 2.4.1 and prior.

The `authenticate.php` file uses the `user` HTTP POST parameter in a call
to the `shell_exec()` PHP function without appropriate input validation,
allowing arbitrary command execution as the apache user.

The sudo configuration permits the apache user to execute any command
as root without providing a password, resulting in privileged command
execution as root.

This module has been successfully tested on Klog Server version 2.4.1
virtual appliance.
Title
Rapid7 Labs

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