Suspicious Gammadyne Mailer Execution for Direct-to-MX Spam

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1566Phishing
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of the Gammadyne Mailer utility, matching the direct-to-MX spam blast run from a compromised terminal server in a phishing stager intrusion. Adversaries use this bulk mailer to send high volumes of outbound SMTP directly to recipient mail exchangers, bypassing corporate mail gateways. Its presence on a server is a strong indicator of abuse for mass phishing.

Reporting behind it

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Suspicious Gammadyne Mailer Execution for Direct-to-MX Spam

Pivot detection · T1566 · 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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