Decode Base64 Encoded Text

 1title: Decode Base64 Encoded Text
 2id: e2072cab-8c9a-459b-b63c-40ae79e27031
 3status: test
 4description: Detects usage of base64 utility to decode arbitrary base64-encoded text
 5references:
 6    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1027/T1027.md
 7author: Daniil Yugoslavskiy, oscd.community
 8date: 2020/10/19
 9modified: 2021/11/27
10tags:
11    - attack.defense_evasion
12    - attack.t1027
13logsource:
14    category: process_creation
15    product: linux
16detection:
17    selection:
18        Image|endswith: '/base64'
19        CommandLine|contains: '-d' # Also covers "--decode"
20    condition: selection
21falsepositives:
22    - Legitimate activities
23level: low

References

• atomic-red-team/atomics/T1027/T1027.md at f339e7da7d05f6057fdfcdd3742bfcf365fee2a9 · redcanaryco/atomic-red-team

  

  Small and highly portable detection tests based on MITRE's ATT&CK. - redcanaryco/atomic-red-team

  
  Read More

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