2. Processes
Take a look to what processes are being executed and check if any process has more privileges than it should (maybe a tomcat being executed by root?)
ps aux
ps -ef
top -n 1
Always check for possible - https://book.hacktricks.xyz/linux-hardening/privilege-escalation/electron-cef-chromium-debugger-abuse Linpeas detect those by checking the --inspect parameter inside the command line of the process. Also check your privileges over the processes binaries, maybe you can overwrite someone.