CHAIN-194 — CI/CD service principal with sub-wide Contributor

Summary

Severity: Critical · Likelihood: High · Logic: ALL

Why this chain matters

The CI/CD deployment SP holds Contributor at subscription scope AND its secret is static. Any PR-triggered workflow has the ability to read/write any resource in the subscription — a malicious PR becomes a subscription takeover.

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_id_008	Trigger
zt_id_001	Trigger

Attack walkthrough

Step 1 — Open a PR that modifies workflow to run attacker code.

Actor: Attacker
MITRE ATT&CK: T1195.002
Enabled by: zt_id_008

Attacker gain: Code execution with SP credential.

Step 2 — SP has Contributor on entire subscription; exfiltrate.

Actor: Attacker
MITRE ATT&CK: T1078
Enabled by: zt_id_001

Attacker gain: Subscription-wide access.

Blast radius

Initial access	Any PR to CI repo.
Max privilege	Subscription Contributor.
Data at risk	Every resource in the subscription
Services at risk	Azure RBAC

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.