Malicious ESXi Syslog Redirection to tmp via esxcli

ATT&CK techniques

Recon
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 reconfiguration of the ESXi syslog log directory to a volatile tmp location via esxcli. This behavior matches Akira ransomware operators targeting VMware ESXi who redirect logs to erase forensic evidence before encrypting virtual machines. Pointing syslog at tmp destroys audit trails and is a defense evasion step tied to hypervisor-level ransomware attacks.

Reporting behind it

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Malicious ESXi Syslog Redirection to tmp via esxcli

Pivot detection · T1685 · 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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