Input Capture: GUI Input Capture

Adversaries may mimic common operating system GUI components to prompt users for credentials with a seemingly legitimate prompt. When programs are executed that need additional privileges than are present in the current user context, it is common for the operating system to prompt the user for proper credentials to authorize the elevated privileges for the task (ex: Bypass User Account Control).

Adversaries may mimic this functionality to prompt users for credentials with a seemingly legitimate prompt for a number of reasons that mimic normal usage, such as a fake installer requiring additional access or a fake malware removal suite.[1] This type of prompt can be used to collect credentials via various languages such as AppleScript[2][3][4] and PowerShell.[2][5][4] On Linux systems adversaries may launch dialog boxes prompting users for credentials from malicious shell scripts or the command line (i.e. Unix Shell).[4]

ID: T1056.002
Sub-technique of:  T1056
Platforms: Linux, Windows, macOS
Permissions Required: User
CAPEC ID: CAPEC-659
Contributors: Matthew Molyett, @s1air, Cisco Talos
Version: 1.2
Created: 11 February 2020
Last Modified: 08 March 2022

Procedure Examples

ID Name Description
S0482 Bundlore

Bundlore prompts the user for their credentials.[6]

S0274 Calisto

Calisto presents an input prompt asking for the user's login and password.[7]

S0281 Dok

Dok prompts the user for credentials.[8]

G0085 FIN4

FIN4 has presented victims with spoofed Windows Authentication prompts to collect their credentials.[9][10]

S0278 iKitten

iKitten prompts the user for their credentials.[8]

S0276 Keydnap

Keydnap prompts the users for credentials.[11]

S0455 Metamorfo

Metamorfo has displayed fake forms on top of banking sites to intercept credentials from victims.[12]

S0279 Proton

Proton prompts users for their credentials.[8]

S0692 SILENTTRINITY

SILENTTRINITY's credphisher.py module can prompt a current user for their credentials.[13]

S0658 XCSSET

XCSSET prompts the user to input credentials using a native macOS dialog box leveraging the system process /Applications/Safari.app/Contents/MacOS/SafariForWebKitDevelopment.[14]

Mitigations

ID Mitigation Description
M1017 User Training

Use user training as a way to bring awareness and raise suspicion for potentially malicious events and dialog boxes (ex: Office documents prompting for credentials).

Detection

ID Data Source Data Component
DS0017 Command Command Execution
DS0009 Process Process Creation
DS0012 Script Script Execution

Monitor process execution for unusual programs as well as malicious instances of Command and Scripting Interpreter that could be used to prompt users for credentials. For example, command/script history including abnormal parameters (such as requests for credentials and/or strings related to creating password prompts) may be malicious.[4]

Inspect and scrutinize input prompts for indicators of illegitimacy, such as non-traditional banners, text, timing, and/or sources.

References