Classification:

attack

Tactic:

TA0003-persistence

Technique:

T1556-modify-authentication-process

VIEW RULE IN DATADOG VIEW SIGNALS

Goal

Detect when an M365 Copilot Studio bot experiences an indirect attack as defined by Microsoft’s content safety checks. The Microsoft generated alert attempts identify if an actor embeds instructions to the agent for the purpose of maliciously gaining access to unauthorized data or control of the system.

Strategy

Monitor Microsoft 365 audit logs for when the @CopilotEventData.AccessedResources.Type includes an IndirectAttack flag within the Copilot service logs.

Triage and response

1. Identify what user, {{@usr.id}}, and action triggered the Microsoft content safety alert. The @CopilotEventData.AccessedResources.Name includes the user action which generated the IndirectAttack alert.
2. Determine if the user {{@usr.id}} and the action taken represents malicious behavior for your organization’s bot.
3. If the interaction prompted the bot for unauthorized access or attempted to manipulate the bot, investigate surrounding events for anomalous activity. If necessary, initiate your company’s incident response (IR) process.