Scheduled Task/Job: Cron T1053.003
Tactics: Execution, Persistence, Privilege Escalation
Adversaries may abuse the cron utility to perform task scheduling for initial or recurring execution of malicious code. The cron utility is a time-based job scheduler for Unix-like operating systems. The crontab file contains the schedule of cron entries to be run and the specified times for execution. Any crontab files are stored in operating system-specific file paths.
Events covered
7 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| ESF | exec | Process Execution |
| ESF | write | File Write |
| Linux-Auditd | Event ID 1300 | SYSCALL |
| Linux-Auditd | Event ID 1302 | PATH |
| Linux-Auditd | Event ID 1307 | CWD |
| Sysmon-for-Linux | Event ID 1 | Process Create |
| Sysmon-for-Linux | Event ID 11 | File created |
Authoring guide
These 38 rules share fields, values, and exclusions.
Fields filtered most (39 distinct)
These fields appear most often in rule filters.
Top indicator values (639 distinct)
These values appear most often in rule predicates.
Exclusions (523 distinct)
These values appear most often in top-level exclusions.
Rules under this technique
These vendors publish rules tagged with this technique.
Sigma 6 rules
- Azure Kubernetes CronJob
- Modifying Crontab
- New Cron File Created
- Scheduled Cron Task/Job - Linux
- Scheduled Cron Task/Job - MacOs
- Triple Cross eBPF Rootkit Default Persistence
Elastic 20 rules
- Cron Job Created or Modified
- Cron Tab Creation or Modification via Shell Command
- Executable Bit Set for Potential Persistence Script
- Hidden Payload Executed via Scheduled Job
- Modification of Persistence Relevant Files Detected via Defend for Containers
- Pod or Container Creation with Suspicious Command-Line
- Potential Persistence via Direct Crontab Modification
- Potential Persistence via File Modification
- Potential Persistence via Periodic Tasks
- Potential Privilege Escalation via Root Crontab File Modification
- Potential Redis CONFIG SET Cron Directory Persistence (RedisRaider)
- Privilege Escalation via Root Crontab File Modification
- Scheduled Job Executing Binary in Unusual Location
- Suspicious CronTab Creation or Modification
- Suspicious Echo Execution
- Suspicious Echo or Printf Execution Detected via Defend for Containers
- Suspicious Execution from Foomatic-rip or Cupsd Parent
- Suspicious Network Activity to the Internet by Previously Unknown Executable
- Unsigned or Untrusted binary Execution via Cron
- Unusual Command Execution via Cron
Splunk 10 rules
- Cisco Isovalent - Cron Job Creation
- Cisco Secure Firewall - Wget or Curl Download
- Linux Add Files In Known Crontab Directories
- Linux Adding Crontab Using List Parameter
- Linux At Allow Config File Creation
- Linux Auditd Edit Cron Table Parameter
- Linux Auditd Possible Append Cronjob Entry On Existing Cronjob File
- Linux Edit Cron Table Parameter
- Linux Possible Append Cronjob Entry on Existing Cronjob File
- Linux Possible Cronjob Modification With Editor