Privilege escalation is how an attacker who already has a foothold gains more rights: from a normal user to administrator or root (vertical), or into another user’s account (horizontal).
Common paths on Linux
- Misconfigured
sudorules that allow running shells or editors as root. - Unneeded SUID binaries and writable scripts run by root via cron or systemd.
- Unpatched kernel or setuid vulnerabilities.
- Credentials left in shell history, config files or environment variables.
Common paths on Windows
- Services with weak permissions or unquoted paths.
- Reused local administrator passwords across machines.
- Token impersonation from service accounts.
- Unpatched local privilege escalation vulnerabilities.
Defence
- Patch promptly, especially vulnerabilities listed as known exploited.
- Apply least privilege; audit sudoers, SUID files and service permissions.
- Randomise local admin passwords (for example with Windows LAPS).
- Alert on new admin group membership and unusual process parents.
