Base16 or Base32 Encoding/Decoding Activityedit

Identifies attempts to encode and decode data, a technique adversaries can use to evade detection by host- or network-based security controls.

Rule type: query

Rule indices:

  • auditbeat-*

Severity: low

Risk score: 21

Runs every: 5 minutes

Searches indices from: now-6m (Date Math format, see also Additional look-back time)

Maximum signals per execution: 100

Tags:

  • Elastic
  • Linux

Version: 1

Added (Elastic Stack release): 7.8.0

Potential false positivesedit

Automated tools such as Jenkins may encode or decode files as part of their normal behavior. These events can be filtered by the process executable or username values.

Rule queryedit

event.action:(executed or process_started) and process.name:(base16 or
base32 or base32plain or base32hex)

Threat mappingedit

Framework: MITRE ATT&CKTM