Alert

Description

Alert is an easy-difficulty Linux machine with a website to upload, view, and share markdown files. The site is vulnerable to cross-site scripting (XSS), which is exploited to access an internal page vulnerable to Arbitrary File Read and leveraged to gain access to a password hash. The hash is then cracked to reveal the credentials leveraged to gain SSH access to the target. Enumeration of processes running on the system shows a PHP file that is being executed regularly, which has excessive privileges for the management group our user is a member of and allows us to overwrite the file for code execution as root.