Malicious Cron Execution of Binary from tmp Directory on Linux (via process_creation)

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 cron launching an executable located under /tmp such as /tmp/kernal, the minute-interval persistence used by threat actors exploiting React2Shell (CVE-2025-55182) on Linux hosts. Scheduling a world-writable /tmp binary via cron provides resilient re-execution of dropped backdoors after post-exploitation.

Reporting behind it

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Malicious Cron Execution of Binary from tmp Directory on Linux (via process_creation)

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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