Suspicious Cron Persistence File Creation in System Cron Directories (via file_event)

ATT&CK techniques

Execution → Priv Esc

Recon
Resource Dev
Initial Access
Execution
- T1053.003Cron
Persistence
- T1053.003Cron
Priv Esc
- T1053.003Cron
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation or modification of files under Linux system cron directories that adversaries use for scheduled task persistence. In the Group-IB XMRig covert Linux PAM abuse campaign the miner establishes persistence through cron entries. Because cron persistence survives reboots and blends with legitimate scheduling, monitoring these paths helps surface unauthorized recurring execution.

Reporting behind it

Related detections9 linkedT1053.003 — drag to rearrange

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Suspicious Cron Persistence via etc cron.d tsar (via file_event)

Suspicious Cron Job Executing Binary From var tmp via Process Creation

Suspicious Cron Job Persistence Creation on Linux (via process_creation)

Suspicious Cron Persistence File Created in System Cron Directories

Linux eBPF Backdoor File Persistence via cron.d and sudoers.d (ebpfbackdoor)

Suspicious Cron Persistence File Creation in System Cron Directories (via file_event)

Pivot detection · T1053.003 · 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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