Unusual weak authentication by user

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

N/A (single event)

Deduplication Period

1 Day

Required Data

  • Requires one of the following data sources:
    • Windows Event Collector
      OR
    • XDR Agent

Detection Modules

Identity Analytics

ATT&CK Tactic

Lateral Movement (TA0008)

ATT&CK Technique

Use Alternate Authentication Material (T1550)

Severity

Informational

Description

A user account authenticated to a host via NTLMv1 or LM authentication for the first time in the past 30 days. This may be indicative of an NTLM downgrade attack
A downgrade attack may force the client to authenticate with a weaker hash/protocol (such as NTLMv1 or even LM) instead of NTLMv2.

Attacker's Goals

The attacker attempts to gain access to the accounts.

Investigative actions

  • Audit all login events with a weaker protocol and review any anomalous usage.