Detection Strategy for Input Injection

Technique Detected:  Input Injection | T1674

ID: DET0568
Domains: Enterprise
Analytics: AN1567, AN1568, AN1569
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN1567

Detects suspicious USB HID device enumeration and keystroke injection patterns, such as rapid sequences of input with no user context, scripts executed through simulated keystrokes, or rogue devices presenting themselves as keyboards.

Log Sources
Data Component Name Channel
Drive Creation (DC0042) WinEventLog:System 20001-20003
Process Creation (DC0032) WinEventLog:Security 4688, 4104
Command Execution (DC0064) WinEventLog:PowerShell EventCode=4104
Mutable Elements
Field Description
AuthorizedUSBDevices List of known, legitimate USB vendor/product IDs authorized for use in the enterprise.
ExecutionTimeWindow Restrict detection to times when no user is logged in or activity is outside business hours.
ParentProcessWhitelist List of legitimate parent processes expected to spawn PowerShell or scripting engines.

AN1568

Detects USB HID device enumeration under /sys/bus/usb/devices/ and rapid keystroke injection resulting in command execution such as bash or Python scripts launched without interactive user activity.

Log Sources
Data Component Name Channel
Process Creation (DC0032) auditd:SYSCALL execve: parent process is usb/hid device handler, child process bash/python invoked
Drive Creation (DC0042) linux:syslog New HID device enumeration with type 'keyboard' followed by immediate input injection
Mutable Elements
Field Description
USBVendorIDs Track suspicious or unapproved USB vendor/product IDs.
ScriptExecutionThreshold Time threshold for script execution after HID injection, e.g., less than 10 seconds.

AN1569

Detects abnormal HID device enumeration via I/O Registry (ioreg -p IOUSB) and keystroke injection targeting AppleScript, osascript, or PowerShell equivalents. Defender correlates new USB device connections with rapid script execution.

Log Sources
Data Component Name Channel
Drive Creation (DC0042) macos:unifiedlog New IOUSB keyboard/HID device enumerated with suspicious attributes
Script Execution (DC0029) macos:unifiedlog osascript, AppleScript, or Python execution triggered immediately after HID connection
Mutable Elements
Field Description
AllowedAppleScripts Whitelist of AppleScripts expected in the environment, to minimize false positives.
TimeWindow Timeframe between HID injection and script execution considered suspicious.