Command and Control (TA0011)(external, opens in a new tab or window)
text code block:from logs-endpoint.events.network-* metadata _id, _index, _version | mv_expand event.action | where host.os.type == "linux" and event.type == "start" and event.action == "connection_attempted" and ( process.executable like "/tmp/*" or process.executable like "/var/tmp/*" or process.executable like "/dev/shm/*" or process.executable like "/var/log/*" or process.executable like "/sys/*" or process.executable like "/media/*" or process.executable like "/proc/*" or process.executable like "/var/backups/*" or process.executable like "/var/mail/*" or process.executable like "/var/spool/*" or process.executable like "./*" or process.name like ".*" ) and not ( cidr_match(destination.ip, "10.0.0.0/8", "127.0.0.0/8", "169.254.0.0/16", "172.16.0.0/12", "192.0.0.0/24", "192.0.0.29/32", "192.0.0.8/32", "192.0.0.9/32", "192.0.0.10/32", "192.0.0.170/32", "192.0.0.171/32", "192.0.2.0/24", "192.31.196.0/24", "192.52.193.0/24", "192.168.0.0/16", "192.88.99.0/24", "224.0.0.0/4", "100.64.0.0/10", "192.175.48.0/24", "198.18.0.0/15", "198.51.100.0/24", "203.0.113.0/24", "240.0.0.0/4", "::1", "FE80::/10", "FF00::/8" ) or process.executable like "/tmp/newroot/*" or process.executable like "/tmp/.mount*" or process.executable like "/tmp/go-build*" ) | keep @timestamp, _id, _index, _version, host.os.type, event.type, event.action, process.name, process.executable, destination.ip, agent.id, host.name, event.dataset, data_stream.namespace | stats Esql.event_count = count(), Esql.agent_id_count_distinct = count_distinct(agent.id), Esql.host_name_values = values(host.name), Esql.agent_id_values = values(agent.id), Esql.event_dataset_values = values(event.dataset), Esql.data_stream_namespace_values = values(data_stream.namespace) by process.executable | where Esql.agent_id_count_distinct == 1 and Esql.event_count > 15 // Extract unique values to ECS fields for alerts exclusion | eval agent.id = mv_min(Esql.agent_id_values), host.name = mv_min(Esql.host_name_values) | sort Esql.event_count asc | keep agent.id, host.name, process.executable, Esql.*
Install detection rules in Elastic Security
Detect High Number of Egress Network Connections from Unusual Executable 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).