Reconstructing AI activity in security investigations

Microsoft defines a structured way to rebuild AI interactions into a coherent investigative timeline using scope, context, and signal across security telem

2026-06-13 GIGATAP Team #security
#AI security#Microsoft Security#incident response

AI activity in Microsoft 365 Copilot and Azure AI now generates distributed telemetry across Microsoft Purview, Defender, and Sentinel. The shift is not about detecting more events, but about reconstructing a coherent sequence of what happened: who interacted with AI systems, when it occurred, what resources were accessed, and whether the behavior matches expected use or indicates compromise.

How is AI activity reconstructed in enterprise investigations?#

Investigations start by binding scattered telemetry into a single timeline. Microsoft describes a scope–context–signal model. Scope defines who interacted with AI systems, when the interaction occurred, and which service was used. Context expands into what data and resources were accessed, including exposure risk and alignment with expected behavior. Signal layer adds detection outputs such as prompt injection attempts, anomalous usage patterns, or credential-related alerts. The reconstruction happens when these layers are merged into a single account of activity rather than reviewed as isolated alerts.

The core change is structural. AI telemetry is metadata-first: identity, time, and resource relationships are already embedded across Microsoft security products. Reconstruction becomes an aggregation problem, not a forensics guesswork exercise.

What changed in Microsoft Security Blog guidance?#

The update formalizes AI investigation as a repeatable workflow rather than ad hoc incident review. Security teams are already investigating Copilot and Azure AI usage ranging from prompt injection attempts to unexpected data access. The problem identified is fragmentation: signals exist, but without structure they do not form a reliable narrative.

The proposed approach operationalizes investigation across Microsoft security tooling. Instead of jumping between alerts, investigators follow a consistent sequence across scope, context, and signal. This reduces dependency on manual correlation and improves consistency across incidents involving AI systems.

Definition capsule#

AI activity reconstruction is the process of converting distributed telemetry from AI interactions into a unified investigative timeline that explains identity, action, data access, and risk outcome.

Where telemetry comes from#

AI interaction data is distributed across Microsoft Purview, Microsoft Defender, and Microsoft Sentinel. Each layer contributes a different slice of visibility: governance-level data access, endpoint and identity signals, and aggregated security analytics. The reconstruction model depends on combining these into a single analytical chain rather than treating them as separate monitoring systems.

The approach extends to agent-based AI systems as well. In those cases, investigation includes agent configuration, authorization scope, and verification of whether access patterns match intended behavior.

Comparison: fragmented signals vs reconstructed investigation#

Layer Fragmented view Reconstructed view
Identity Isolated login or prompt event User-to-AI interaction chain
Time Individual timestamps Ordered activity sequence
Data access Single resource alerts Full exposure path across sessions
Detection signals Standalone alerts Interpreted within full context

What investigators should check first#

Scope comes first: who used AI systems, when, and which service endpoint was involved. Without this, context and signal analysis loses structure.

Next is resource mapping: what data was accessed during AI interaction, and whether it aligns with expected permissions. Finally, detection signals such as prompt injection or anomaly alerts are evaluated against the reconstructed sequence rather than treated independently.

This sequence reduces false interpretation of isolated alerts and aligns investigation with actual system behavior rather than reactive alert triage.

Why this matters for security operations#

AI systems are now embedded in everyday workflows, not isolated tools. That changes incident response expectations. Security operations must be able to explain AI behavior in the same way they explain endpoint or identity compromise.

The operational implication is direct: reconstruction becomes a core capability, not an advanced forensic step. Without it, AI-related incidents remain fragmented signals with no reliable narrative.

Internal references:
https://gigatap.top/en/articles/openssfs-april-signal-make-security-artifacts-operational
https://gigatap.top/en/articles/100-package-test-coverage-is-the-point-not-the-slogan
https://gigatap.top/en/articles/open-source-security-needs-more-than-code

FAQ#

What is the main goal of AI activity reconstruction?
To convert distributed telemetry from AI interactions into a coherent timeline that explains identity, actions, data access, and risk context.

Why are traditional alert-based investigations insufficient for AI systems?
Because AI interactions generate cross-system telemetry that cannot be interpreted correctly in isolation; alerts require contextual reconstruction.

How does this change security operations workflows?
It shifts analysis from reactive alert handling to structured reconstruction across identity, resource, and detection layers.

What systems are involved in this model?
Microsoft Purview, Defender, and Sentinel provide the primary telemetry sources used in reconstruction workflows.