Analytics BIOC Informational

VPN login by a dormant user

A dormant user logged on to a VPN service after having been unused for a month or longer. This may indicate the account is misused by an attacker.

Module:
Identity Analytics
Data source:
Palo Alto Networks Global Protect, Third-Party VPNs
ATT&CK tactics: Defense Evasion (TA0005)
ATT&CK techniques: Valid Accounts: Domain Accounts (T1078.002)
Attacker's goals:

Use a compromised user account which has not been used for a long while, and therefore is less likely to be noticed.

Investigative actions:

Confirm that the activity is benign (e.g. the user returned from a long leave of absence). See whether there are other abnormal actions done by the user (e.g. files\commands\other logins). Check if the user initiated other logins aside from a VPN login. Check whether you have issues with your Cloud Identity Engine failing to sync data from Active Directory.

Test period:
N/A (single event)
Deduplication:
1 Day