Decode CEF [processor-decode-cef]

The decode_cef processor decodes Common Event Format (CEF) messages. It follows the specification defined in Micro Focus Security ArcSight Common Event Format, Version 25. This processor is available in Filebeat. This is an example CEF message.

CEF:0|SomeVendor|TheProduct|1.0|100|connection to malware C2 successfully stopped|10|src=192.0.2.10 dst=203.0.113.2 spt=31224

Any content that precedes CEF: is ignored. This allows the processor to directly parse CEF content from messages that contain syslog headers.

Below is an example configuration that decodes the message field as CEF after renaming it to event.original. It is best to rename message to event.original because the decoded CEF data contains its own message field.

yaml

processors:
  - rename:
      fields:
        - {from: "message", to: "event.original"}
  - decode_cef:
      field: event.original

The decode_cef processor has the following configuration settings.

Name	Required	Default	Description
`field`	no	message	Source field containing the CEF message to be parsed.
`target_field`	no	cef	Target field where the parsed CEF object will be written.
`ecs`	no	true	Generate Elastic Common Schema (ECS) fields from the CEF data. Certain CEF header and extension values will be used to populate ECS fields.
`timezone`	no	UTC	IANA time zone name (e.g. `America/New_York`) or fixed time offset (e.g. `+0200`) to use when parsing times that do not contain a time zone. `Local` may be specified to use the machine’s local time zone.
`ignore_missing`	no	false	Ignore errors when the source field is missing.
`ignore_failure`	no	false	Ignore failures when the source field does not contain a CEF message.
`ignore_empty_values`	no	false	Ignore CEF extensions with empty values (e.g. `spt= type=1`)
`id`	no		An identifier for this processor instance. Useful for debugging.