Find sigma rule 
Attack: Valid Accounts: Local Accounts
Adversaries may obtain and abuse credentials of a local account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Local accounts are those configured by an organization for use by users, remote support, services, or for administration on a single system or service.
Local Accounts may also be abused to elevate privileges and harvest credentials through OS Credential Dumping. Password reuse may allow the abuse of local accounts across a set of machines on a network for the purposes of Privilege Escalation and Lateral Movement.
MITRE
Tactic
- defense-evasion
- persistence
- privilege-escalation
- initial-access
technique
- T1078.003
Test : Login as nobody (Linux)
OS
- linux
Description:
An adversary may try to re-purpose a system account to appear legitimate. In this test change the login shell of the nobody account, change its password to nobody, su to nobody, exit, then reset nobody’s shell to /usr/sbin/nologin.
Executor
bash