Suspicious Access to IIS machine.config outside the Worker Process Context (via security)

ATT&CK techniques

Persistence → Cred Access

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505.003Web Shell
Priv Esc
Defense Evasion
Cred Access
- T1552Unsecured Credentials
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects object-access auditing events for web.config or machine.config performed by a process other than the IIS worker or expected build tooling, a hunting signal for adversaries harvesting the validationKey and decryptionKey values that enable ViewState code-injection attacks. Stolen or leaked machine keys let attackers forge authenticated ViewState payloads, so unexpected reads of these files can reveal key theft before exploitation.

Reporting behind it

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Suspicious Access to IIS machine.config outside the Worker Process Context (via security)

Pivot detection · T1505.003 · 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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