Data Encoding T1132
Tactic: Command & Control
Adversaries may encode data to make the content of command and control traffic more difficult to detect. Command and control (C2) information can be encoded using a standard data encoding system. Use of data encoding may adhere to existing protocol specifications and includes use of ASCII, Unicode, Base64, MIME, or other binary-to-text and character encoding systems. Some data encoding systems may also result in data compression, such as gzip.
Events covered
5 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| ESF | exec | Process Execution |
| PowerShell | Event ID 4103 | Payload Context: ContextInfo User Data: UserData. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
Authoring guide
These 15 rules share fields, values, and exclusions.
Fields filtered most (15 distinct)
These fields appear most often in rule filters.
Top indicator values (77 distinct)
These values appear most often in rule predicates.
Exclusions (2 distinct)
These values appear most often in top-level exclusions.
Rules under this technique
These vendors publish rules tagged with this technique.
Sigma 4 rules
- DNS Exfiltration and Tunneling Tools Execution
- Gzip Archive Decode Via PowerShell
- Suspicious FromBase64String Usage On Gzip Archive - Process Creation
- Suspicious FromBase64String Usage On Gzip Archive - Ps Script
Elastic 3 rules
- Base16 or Base32 Encoding/Decoding Activity
- Empire Stager Execution
- File Compressed or Archived into Common Format by Unsigned Process
Splunk 5 rules
- Certutil Execution (Sysmon)
- Certutil Execution (Windows Event Log)
- Certutil Obfuscate_Encode Files (PowerShell)
- Certutil Obfuscate_Encode Files (Sysmon)
- Certutil Obfuscate_Encode Files (Windows Event Log)