Defense Evasion (TA0005)(external, opens in a new tab or window)
text code block:process where host.os.type == "linux" and event.type == "start" and event.action == "exec" and process.parent.name == "busybox" and process.name in ("bash", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and process.command_line in ("bash", "bash-", "dash", "sh", "tcsh", "csh", "zsh", "ksh", "fish") and not ( process.args == "-c" or process.parent.args : ( "crond", "/usr/sbin/crond", "/local-registrator.sh", "/var/atlassian/application-data/bamboo-agent*" ) or process.parent.command_line in ( "sh /readonly-config/fix-split-brain.sh", "/bin/sh -c /health-check.sh || bash -c 'kill -s 15 $(pidof siridb-server) && (sleep 10; kill -s 9 $(pidof siridb-server))'" ) or process.command_line == "bash /etc/kafka/docker/run" or process.parent.command_line like ( "/bin/sh -c apk add*", "/bin/sh -c crm-cron-enabled*", "udhcpc -n -p /run/udhcpc.*", "flock -x*" ) or process.working_directory == "/usr/share/grafana" )
Install detection rules in Elastic Security
Detect Proxy Shell Execution via Busybox in the Elastic Security detection engine by installing this rule into your Elastic Stack.
To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).