T1056.004 Input Capture: Credential API Hooking — cross-source coverage

From MITRE ATT&CK 19.2

Adversaries may hook into Windows application programming interface (API) functions and Linux system functions to collect user credentials. Malicious hooking mechanisms may capture API or function calls that include parameters that reveal user authentication credentials. Unlike Keylogging, this technique focuses specifically on API functions that include parameters that reveal user credentials.

In Windows, hooking involves redirecting calls to these functions and can be implemented via:

Hooks procedures, which intercept and execute designated code in response to events such as messages, keystrokes, and mouse inputs.
Import address table (IAT) hooking, which use modifications to a process’s IAT, where pointers to imported API functions are stored.
Inline hooking, which overwrites the first bytes in an API function to redirect code flow.

In Linux and macOS, adversaries may hook into system functions via the LD_PRELOAD (Linux) or DYLD_INSERT_LIBRARIES (macOS) environment variables, which enables loading shared libraries into a program’s address space. For example, an adversary may capture credentials by hooking into the libc read function leveraged by SSH or SCP.

Tactics

Collection · Credential Access

Platforms

Windows · Linux · macOS

Telemetry

WinEventLog:Sysmonauditd:SYSCALLmacos:unifiedlogfs:fsusagemacos:osquery

How MITRE says to detect it DET0139

Detection of Credential Harvesting via API Hooking

Windows Analytic 0389

Detects credential harvesting via userland API hooking (e.g., SetWindowsHookEx, IAT, or inline patching) by correlating memory modifications with hook installation functions and suspicious module loads in credential-sensitive processes like lsass.exe, explorer.exe, or winlogon.exe.

WinEventLog:Sysmon EventCode=10
WinEventLog:Sysmon EventCode=7
WinEventLog:Sysmon EventCode=8

Linux Analytic 0390

Detects credential interception via malicious LD_PRELOAD-based shared libraries loaded into ssh, sudo, or scp processes. Correlates environment variable injection, unexpected library loads, and memory patching behavior.

auditd:SYSCALL execve
auditd:SYSCALL LD_PRELOAD Logging

macOS Analytic 0391

Detects DYLD_INSERT_LIBRARIES abuse to hook credential-sensitive applications by correlating process spawns with unauthorized library injection and monitoring changes to the __TEXT segment (code) of credential handling binaries.

macos:unifiedlog DYLD event subsystem
fs:fsusage File Access Monitor
macos:osquery Memory Mappings