title: Junk Code Insertion (T1027.016)
id: df00tech-t1027-016
status: experimental
description: "Adversaries may insert junk code or dead code into malware to obfuscate its functionality, hinder static analysis, and evade signature-based detections. Junk code includes NOP (No-Operation) sleds, dummy API calls, excessive mathematical operations, infinite loops that are never reached, and random garbage instructions interspersed between legitimate code. Unlike Binary Padding (T1027.001), which changes file size/hash, junk code insertion specifically targets analyst workflow and automated analysis engines. Real-world actors including Maze ransomware, FIN7, Gamaredon Group, APT32, Kimsuky, and StrelaStealer have employed this technique."
references:
  - https://attack.mitre.org/techniques/T1027/016/
  - https://df00tech.com/detections/T1027.016
author: df00tech
date: 2026/04/13
tags:
  - attack.t1027.016
# NOTE: logsource is auto-derived and may need adjustment for your environment
logsource:
  category: process_creation
  product: windows
detection:
  # This detection logic could not be auto-translated; see the KQL/SPL query on df00tech.
  selection:
    EventID: '*'
  condition: selection
falsepositives:
  - "Legitimate software installers that extract temporary executables to %TEMP% directories during installation (e.g., NSIS, Inno Setup installers)"
  - "Developer tools and build systems (MSBuild, Roslyn compilers) generating intermediate binaries without version metadata in temp directories"
  - Scripting automation tools using heavy string concatenation for legitimate data manipulation or template generation
  - Third-party software lacking version information metadata (many open-source or legacy applications omit this field)
  - Security testing tools and penetration testing frameworks that intentionally lack signatures
level: medium