Possible CVE-2023-23397 Outlook Forced Authentication via Outbound LDAP (via network_connection)

ATT&CK techniques

Cred Access

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1187Forced Authentication
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a Windows host initiating an outbound LDAP or Global Catalog connection to a non-private external address, which is anomalous because directory traffic normally stays inside the enterprise. Exploitation of CVE-2023-23397 can direct a client to an external LDAP endpoint as part of the forced authentication chain against Microsoft Outlook. Traffic to an external directory service indicates possible credential coercion or beaconing and warrants investigation.

Reporting behind it

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Possible CVE-2023-23397 Outlook Forced Authentication via Outbound LDAP (via network_connection)

Pivot detection · T1187 · 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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