type: attack-pattern
spec_version: 2.1
id: attack-pattern--f5946b5e-9408-485f-a7f7-b5efc88909b6
created: 2020-02-11T19:01:15.930Z
created_by_ref: identity--c78cb6e5-0c4b-4611-8297-d1b8b55e40b5
revoked: no
external_references: source_name: mitre-attack
url: https://attack.mitre.org/techniques/T1056/004
external_id: T1056.004
source_name: EyeofRa Detecting Hooking June 2017
description: Eye of Ra. (2017, June 27). Windows Keylogger Part 2: Defense against user-land. Retrieved December 12, 2017.
url: https://eyeofrablog.wordpress.com/2017/06/27/windows-keylogger-part-2-defense-against-user-land/
source_name: Zairon Hooking Dec 2006
description: Felici, M. (2006, December 6). Any application-defined hook procedure on my machine?. Retrieved December 12, 2017.
url: https://zairon.wordpress.com/2006/12/06/any-application-defined-hook-procedure-on-my-machine/
source_name: GMER Rootkits
description: GMER. (n.d.). GMER. Retrieved December 12, 2017.
url: http://www.gmer.net/
source_name: MWRInfoSecurity Dynamic Hooking 2015
description: Hillman, M. (2015, August 8). Dynamic Hooking Techniques: User Mode. Retrieved December 20, 2017.
url: https://www.mwrinfosecurity.com/our-thinking/dynamic-hooking-techniques-user-mode/
source_name: Elastic Process Injection July 2017
description: Hosseini, A. (2017, July 18). Ten Process Injection Techniques: A Technical Survey Of Common And Trending Process Injection Techniques. Retrieved December 7, 2017.
url: https://www.endgame.com/blog/technical-blog/ten-process-injection-techniques-technical-survey-common-and-trending-process
source_name: Intezer Symbiote 2022
description: Joakim Kennedy and The BlackBerry Threat Research & Intelligence Team. (2022, June 9). Symbiote Deep-Dive: Analysis of a New, Nearly-Impossible-to-Detect Linux Threat. Retrieved March 24, 2025.
url: https://intezer.com/blog/research/new-linux-threat-symbiote/
source_name: HighTech Bridge Inline Hooking Sept 2011
description: Mariani, B. (2011, September 6). Inline Hooking in Windows. Retrieved November 17, 2024.
url: https://www.scribd.com/document/68671361/Inline-Hooking-in-Windows
source_name: Microsoft TrojanSpy:Win32/Ursnif.gen!I Sept 2017
description: Microsoft. (2017, September 15). TrojanSpy:Win32/Ursnif.gen!I. Retrieved December 18, 2017.
url: https://www.microsoft.com/en-us/wdsi/threats/malware-encyclopedia-description?Name=TrojanSpy:Win32/Ursnif.gen!I&threatId=-2147336918
source_name: Microsoft Hook Overview
description: Microsoft. (n.d.). Hooks Overview. Retrieved December 12, 2017.
url: https://msdn.microsoft.com/library/windows/desktop/ms644959.aspx
source_name: Microsoft Process Snapshot
description: Microsoft. (n.d.). Taking a Snapshot and Viewing Processes. Retrieved December 12, 2017.
url: https://msdn.microsoft.com/library/windows/desktop/ms686701.aspx
source_name: PreKageo Winhook Jul 2011
description: Prekas, G. (2011, July 11). Winhook. Retrieved December 12, 2017.
url: https://github.com/prekageo/winhook
source_name: Jay GetHooks Sept 2011
description: Satiro, J. (2011, September 14). GetHooks. Retrieved December 12, 2017.
url: https://github.com/jay/gethooks
source_name: StackExchange Hooks Jul 2012
description: Stack Exchange - Security. (2012, July 31). What are the methods to find hooked functions and APIs?. Retrieved December 12, 2017.
url: https://security.stackexchange.com/questions/17904/what-are-the-methods-to-find-hooked-functions-and-apis
source_name: Adlice Software IAT Hooks Oct 2014
description: Tigzy. (2014, October 15). Userland Rootkits: Part 1, IAT hooks. Retrieved December 12, 2017.
url: https://www.adlice.com/userland-rootkits-part-1-iat-hooks/
source_name: Volatility Detecting Hooks Sept 2012
description: Volatility Labs. (2012, September 24). MoVP 3.1 Detecting Malware Hooks in the Windows GUI Subsystem. Retrieved December 12, 2017.
url: https://volatility-labs.blogspot.com/2012/09/movp-31-detecting-malware-hooks-in.html
object_marking_refs: marking-definition--fa42a846-8d90-4e51-bc29-71d5b4802168
modified: 2025-10-24T17:49:37.119Z
name: Credential API Hooking
description: 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.(Citation: Microsoft TrojanSpy:Win32/Ursnif.gen!I Sept 2017) Unlike [Keylogging](https://attack.mitre.org/techniques/T1056/001), 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.(Citation: Microsoft Hook Overview)(Citation: Elastic Process Injection July 2017)
* **Import address table (IAT) hooking**, which use modifications to a process’s IAT, where pointers to imported API functions are stored.(Citation: Elastic Process Injection July 2017)(Citation: Adlice Software IAT Hooks Oct 2014)(Citation: MWRInfoSecurity Dynamic Hooking 2015)
* **Inline hooking**, which overwrites the first bytes in an API function to redirect code flow.(Citation: Elastic Process Injection July 2017)(Citation: HighTech Bridge Inline Hooking Sept 2011)(Citation: MWRInfoSecurity Dynamic Hooking 2015)

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.(Citation: Intezer Symbiote 2022)
kill_chain_phases: kill_chain_name: mitre-attack
phase_name: collection
kill_chain_name: mitre-attack
phase_name: credential-access
x_mitre_attack_spec_version: 3.2.0
x_mitre_deprecated: no
x_mitre_domains: enterprise-attack
x_mitre_is_subtechnique: yes
x_mitre_modified_by_ref: identity--c78cb6e5-0c4b-4611-8297-d1b8b55e40b5
x_mitre_platforms: Windows
Linux
macOS
x_mitre_version: 1.2