CHAIN-145 — Bot Service app registration over-privileged

Summary

Severity: Medium · Likelihood: Medium · Logic: ALL

Why this chain matters

An Azure Bot Service registration has application permissions including User.Read.All and Channel.ReadAll — far more than needed for its normal Q&A chatbot function. A compromise of the bot's service principal yields tenant-wide read of user directory data.

Component rules

This chain fires when its trigger conditions are met by the following rules. Click any rule to see its detection logic and compliance mappings.

Rule ID	Role
zt_ai_004	Trigger
zt_id_011	Trigger

Attack walkthrough

Step 1 — Compromise the bot's App Service via any web vuln.

Actor: Attacker
MITRE ATT&CK: T1190
Enabled by: zt_ai_004

Attacker gain: Bot SP access.

Step 2 — Call /users and /channels via Graph; exfil directory.

Actor: Attacker
MITRE ATT&CK: T1087.004
Enabled by: zt_id_011

Attacker gain: Entra directory read.

Blast radius

Initial access	Bot compromise.
Max privilege	Directory read + channel read.
Data at risk	Directory objects, Teams channels
Services at risk	Entra ID + Teams

How the logic works

The chain fires only when every rule above has at least one finding in the current scan. Missing any one rule breaks the chain — so remediating any single step disrupts the attack path.