Falco Examples
Here are some examples of the types of behavior falco can detect.
For a more comprehensive set of examples, see the full rules file at falco_rules.yaml
.
A shell is run in a container
- macro: container
condition: container.id != host
- macro: spawned_process
condition: evt.type = execve and evt.dir=<
- rule: run_shell_in_container
desc: a shell was spawned by a non-shell program in a container. Container entrypoints are excluded.
condition: container and proc.name = bash and spawned_process and proc.pname exists and not proc.pname in (bash, docker)
output: "Shell spawned in a container other than entrypoint (user=%user.name container_id=%container.id container_name=%container.name shell=%proc.name parent=%proc.pname cmdline=%proc.cmdline)"
priority: WARNING
Unexpected outbound Elasticsearch connection
- macro: outbound
condition: syscall.type=connect and evt.dir=< and (fd.typechar=4 or fd.typechar=6)
- macro: elasticsearch_cluster_port
condition: fd.sport=9300
- rule: elasticsearch_unexpected_network_outbound
desc: outbound network traffic from elasticsearch on a port other than the standard ports
condition: user.name = elasticsearch and outbound and not elasticsearch_cluster_port
output: "Outbound network traffic from Elasticsearch on unexpected port (connection=%fd.name)"
priority: WARNING
Write to directory holding system binaries
- macro: open_write
condition: >
(evt.type=open or evt.type=openat) and
fd.typechar='f' and
(evt.arg.flags contains O_WRONLY or
evt.arg.flags contains O_RDWR or
evt.arg.flags contains O_CREAT or
evt.arg.flags contains O_TRUNC)
- macro: package_mgmt_binaries
condition: proc.name in (dpkg, dpkg-preconfigu, rpm, rpmkey, yum)
- macro: bin_dir
condition: fd.directory in (/bin, /sbin, /usr/bin, /usr/sbin)
- rule: write_binary_dir
desc: an attempt to write to any file below a set of binary directories
condition: evt.dir = < and open_write and not proc.name in (package_mgmt_binaries) and bin_dir
output: "File below a known binary directory opened for writing (user=%user.name command=%proc.cmdline file=%fd.name)"
priority: WARNING
Non-authorized container namespace change
- rule: change_thread_namespace
desc: an attempt to change a program/thread\'s namespace (commonly done as a part of creating a container) by calling setns.
condition: syscall.type = setns and not proc.name in (docker, sysdig, dragent)
output: "Namespace change (setns) by unexpected program (user=%user.name command=%proc.cmdline container=%container.id)"
priority: WARNING
Non-device files written in /dev (some rootkits do this)
- rule: create_files_below_dev
desc: creating any files below /dev other than known programs that manage devices. Some rootkits hide files in /dev.
condition: (evt.type = creat or evt.arg.flags contains O_CREAT) and proc.name != blkid and fd.directory = /dev and fd.name != /dev/null
output: "File created below /dev by untrusted program (user=%user.name command=%proc.cmdline file=%fd.name)"
priority: WARNING
Process other than skype/webex tries to access camera
- rule: access_camera
desc: a process other than skype/webex tries to access the camera
condition: evt.type = open and fd.name = /dev/video0 and not proc.name in (skype, webex)
output: Unexpected process opening camera video device (command=%proc.cmdline)
priority: WARNING
Feedback
Was this page helpful?
Glad to hear it! Please tell us how we can improve.
Sorry to hear that. Please tell us how we can improve.
Last modified February 14, 2022: updated suggestion (04b2268)