MITRE ATT&CK Technique
Credential Access T1556
Description

Adversaries may modify authentication mechanisms and processes to access user credentials or enable otherwise unwarranted access to accounts. The authentication process is handled by mechanisms, such as the Local Security Authentication Server (LSASS) process and the Security Accounts Manager (SAM) on Windows, pluggable authentication modules (PAM) on Unix-based systems, and authorization plugins on MacOS systems, responsible for gathering, storing, and validating credentials. By modifying an authentication process, an adversary may be able to authenticate to a service or system without using [Valid Accounts](https://attack.mitre.org/techniques/T1078). Adversaries may maliciously modify a part of this process to either reveal credentials or bypass authentication mechanisms. Compromised credentials or access may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access and remote desktop.

Supported Platforms
Windows Linux macOS Network Devices IaaS SaaS Office Suite Identity Provider
Created

April 29, 2026

Last Updated

April 29, 2026

STIX Data
{'created': '2020-02-11T19:01:56.887Z',
 'created_by_ref': 'identity--c78cb6e5-0c4b-4611-8297-d1b8b55e40b5',
 'description': 'Adversaries may modify authentication mechanisms and '
                'processes to access user credentials or enable otherwise '
                'unwarranted access to accounts. The authentication process is '
                'handled by mechanisms, such as the Local Security '
                'Authentication Server (LSASS) process and the Security '
                'Accounts Manager (SAM) on Windows, pluggable authentication '
                'modules (PAM) on Unix-based systems, and authorization '
                'plugins on MacOS systems, responsible for gathering, storing, '
                'and validating credentials. By modifying an authentication '
                'process, an adversary may be able to authenticate to a '
                'service or system without using [Valid '
                'Accounts](https://attack.mitre.org/techniques/T1078).\n'
                '\n'
                'Adversaries may maliciously modify a part of this process to '
                'either reveal credentials or bypass authentication '
                'mechanisms. Compromised credentials or access may be used to '
                'bypass access controls placed on various resources on systems '
                'within the network and may even be used for persistent access '
                'to remote systems and externally available services, such as '
                'VPNs, Outlook Web Access and remote desktop.',
 'external_references': [{'external_id': 'T1556',
                          'source_name': 'mitre-attack',
                          'url': 'https://attack.mitre.org/techniques/T1556'},
                         {'description': 'Bialek, J. (2013, September 15). '
                                         'Intercepting Password Changes With '
                                         'Function Hooking. Retrieved November '
                                         '21, 2017.',
                          'source_name': 'Clymb3r Function Hook Passwords Sept '
                                         '2013',
                          'url': 'https://clymb3r.wordpress.com/2013/09/15/intercepting-password-changes-with-function-hooking/'},
                         {'description': 'Chris Ross. (2018, October 17). '
                                         'Persistent Credential Theft with '
                                         'Authorization Plugins. Retrieved '
                                         'April 22, 2021.',
                          'source_name': 'Xorrior Authorization Plugins',
                          'url': 'https://xorrior.com/persistent-credential-theft/'},
                         {'description': 'Dell SecureWorks. (2015, January '
                                         '12). Skeleton Key Malware Analysis. '
                                         'Retrieved April 8, 2019.',
                          'source_name': 'Dell Skeleton',
                          'url': 'https://www.secureworks.com/research/skeleton-key-malware-analysis'},
                         {'description': 'Metcalf, S. (2015, November 22). '
                                         'Dump Clear-Text Passwords for All '
                                         'Admins in the Domain Using Mimikatz '
                                         'DCSync. Retrieved November 15, 2021.',
                          'source_name': 'dump_pwd_dcsync',
                          'url': 'https://adsecurity.org/?p=2053'},
                         {'description': 'Microsoft. (2016, April 15). Audit '
                                         'Policy Recommendations. Retrieved '
                                         'June 3, 2016.',
                          'source_name': 'TechNet Audit Policy',
                          'url': 'https://technet.microsoft.com/en-us/library/dn487457.aspx'}],
 'id': 'attack-pattern--f4c1826f-a322-41cd-9557-562100848c84',
 'kill_chain_phases': [{'kill_chain_name': 'mitre-attack',
                        'phase_name': 'credential-access'},
                       {'kill_chain_name': 'mitre-attack',
                        'phase_name': 'defense-evasion'},
                       {'kill_chain_name': 'mitre-attack',
                        'phase_name': 'persistence'}],
 'modified': '2025-10-24T17:49:36.944Z',
 'name': 'Modify Authentication Process',
 'object_marking_refs': ['marking-definition--fa42a846-8d90-4e51-bc29-71d5b4802168'],
 'revoked': False,
 'spec_version': '2.1',
 'type': 'attack-pattern',
 'x_mitre_attack_spec_version': '3.2.0',
 'x_mitre_contributors': ['Chris Ross @xorrior'],
 'x_mitre_deprecated': False,
 'x_mitre_detection': '',
 'x_mitre_domains': ['enterprise-attack'],
 'x_mitre_is_subtechnique': False,
 'x_mitre_modified_by_ref': 'identity--c78cb6e5-0c4b-4611-8297-d1b8b55e40b5',
 'x_mitre_platforms': ['Windows',
                       'Linux',
                       'macOS',
                       'Network Devices',
                       'IaaS',
                       'SaaS',
                       'Office Suite',
                       'Identity Provider'],
 'x_mitre_version': '2.6'}
Quick Actions
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