Suspicious Linux Crontab Reboot Persistence to Hidden Sys Cache Binary (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 the installation of a crontab reboot entry pointing to a hidden .Sys_cache binary under var tmp as used by the Linux SSH CoinMiner campaign. Piping a modified crontab that adds a reboot job to a hidden file is a common miner persistence technique.

Reporting behind it

Related detections9 linkedT1053.003 — drag to rearrange

Suspicious Cron Job Downloading and Executing Payload via GlobalProtect Exploitation

Suspicious Remote Script Download Piped to Shell via 8220 Gang Hadooken

Suspicious Cron Persistence Installing a Downloader via Command Line

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

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 Linux Crontab Reboot Persistence to Hidden Sys Cache Binary (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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