Multiple TGT requests for users without Kerberos pre-authentication

Cortex XDR Analytics Alert Reference by Alert name

Product
Cortex XDR
Last date published
2024-06-04
Category
Analytics Alert Reference
Order
Alert name

Synopsis

Activation Period

14 Days

Training Period

30 Days

Test Period

10 Minutes

Deduplication Period

1 Day

Required Data

  • Requires one of the following data sources:
    • Windows Event Collector
      OR
    • XDR Agent
  • Requires:
    • eXtended Threat Hunting (XTH)

Detection Modules

Identity Analytics

ATT&CK Tactic

Credential Access (TA0006)

ATT&CK Technique

Steal or Forge Kerberos Tickets: AS-REP Roasting (T1558.004)

Severity

Informational

Description

Multiple TGT requests for users that do not require Kerberos pre-authentication were observed. This is typically a sign of an AS-REP attack.

Attacker's Goals

Crack account credentials by obtaining an easy-to-crack Kerberos ticket.

Investigative actions

Check who used the host at the time of the alert, to rule out a benign service or tool requesting weak Kerberos encryption.

Variations

An excessive number of TGT requests were sent for users that do not require Kerberos pre-authentication

Synopsis

ATT&CK Tactic

Credential Access (TA0006)

ATT&CK Technique

Steal or Forge Kerberos Tickets: AS-REP Roasting (T1558.004)

Severity

Low

Description

Multiple TGT requests for users that do not require Kerberos pre-authentication were observed. This is typically a sign of an AS-REP attack.

Attacker's Goals

Crack account credentials by obtaining an easy-to-crack Kerberos ticket.

Investigative actions

Check who used the host at the time of the alert, to rule out a benign service or tool requesting weak Kerberos encryption.


A TGT request was sent for a user who does not require Kerberos pre-authentication

Synopsis

ATT&CK Tactic

Credential Access (TA0006)

ATT&CK Technique

Steal or Forge Kerberos Tickets: AS-REP Roasting (T1558.004)

Severity

Informational

Description

A TGT request was sent for a user who does not require Kerberos pre-authentication. This might indicate an AS-REP attack.

Attacker's Goals

Crack account credentials by obtaining an easy-to-crack Kerberos ticket.

Investigative actions

Check who used the host at the time of the alert, to rule out a benign service or tool requesting weak Kerberos encryption.