Malicious Unsigned VIB Installation on ESXi Host via esxcli (via process_creation)

ATT&CK techniques

Persistence

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1505Server Software Component
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects installation of a VMware Installation Bundle on an ESXi host with signature verification bypassed through a forced or no signature check flag. Fire Ant deployed malicious unsigned VIB packages with a lowered acceptance level to gain persistence beneath the hypervisor. Forcing unsigned package installation is rarely part of legitimate ESXi maintenance.

Reporting behind it

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Malicious Unsigned VIB Installation on ESXi Host via esxcli (via process_creation)

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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