The rule titled "At Job Created or Modified" is designed to detect suspicious creation or modification of at jobs in Linux systems. At jobs, which are scheduled tasks in Linux, can be utilized by legitimate system administrators for routine automation. However, when manipulated by malicious actors, they can serve as vectors for persistence, privilege escalation, and executing unauthorized commands or scripts at predefined intervals. The rule inspects logs for file events specifically associated with the '/var/spool/cron/atjobs/' directory. It excludes benign processes commonly known to create or modify such jobs, thus focusing on potential misuse. The specified EQL (Elastic Query Language) query looks for events indicating the creation or renaming of files in that directory, establishing a baseline for normal activity to help identify nefarious usage. The rule is part of a proactive threat detection strategy, facilitating quick response to potential threats of unauthorized access and exploitation.