1200kmSECURITY RESEARCH

1200KM / sigma-rule

Decode Base64 Encoded Text — Sigma Rule

Sigma rule e2072cab-8c9a-459b-b63c-40ae79e27031. Decode Base64 Encoded Text — Sigma Rule. Detects usage of base64 utility to decode arbitrary base64-encoded text

Rule metadata and linked tags

Author: Daniil Yugoslavskiy, oscd.community. Source status: test; severity: low. Source dates: 2020-10-19 / 2021-11-27.

{
  "category": "process_creation",
  "product": "linux"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 5f19210a426f49e15a3906295928895f4d5e81800f9eb5a2328ce973cfc50d48

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Decode Base64 Encoded Text
id: e2072cab-8c9a-459b-b63c-40ae79e27031
status: test
description: Detects usage of base64 utility to decode arbitrary base64-encoded text
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1027/T1027.md
author: Daniil Yugoslavskiy, oscd.community
date: 2020-10-19
modified: 2021-11-27
tags:
    - attack.stealth
    - attack.t1027
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/base64'
        CommandLine|contains: '-d' # Also covers "--decode"
    condition: selection
falsepositives:
    - Legitimate activities
level: low

Original YAML and metadata in JSON

False positives

  • Legitimate activities

Source references

Connected ecosystem references

Exact source-tagged techniques

Telemetry review

Read the original logsource above, then inspect the linked detection workspaces for technique-level sensor context. No per-rule telemetry equivalence is inferred.

Pinned research references. No browser attack runner, live simulation result or validated detector is asserted. Source mappings and validation limits are preserved. ATT&CK / Atomic provenance · Detection provenance.