Suspicious Kerberos Encryption Downgrade via msDS-SupportedEncryptionTypes
- Product
- windows
- Service
- security
- Author
- HuntRule
- Published
- 2026-10-30
- Updated
- 2026-10-30
ATT&CK techniques
Cred AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects modification of the msDS-SupportedEncryptionTypes attribute on an account object. Adversaries downgrade an account to weaker RC4 encryption to enable offline cracking of Kerberos tickets and to weaken authentication protections.
Reporting behind it
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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