Suspicious Bun Runtime Spawned by Node During npm Lifecycle

ATT&CK techniques

Initial Access → Execution

Recon
Resource Dev
Initial Access
- T1195.002Compromise Software Supply Chain
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects the Node.js process launching the Bun JavaScript runtime, a chain observed when malicious npm packages execute payloads through Bun during install or lifecycle events. It is associated with software supply chain attacks that weaponize trusted developer workflows to run code on build and developer hosts. Detecting this uncommon parent-child pair surfaces post-install package execution abuse.

Reporting behind it

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Suspicious Bun Runtime Spawned by Node During npm Lifecycle

Pivot detection · T1059.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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