THREATNOIR
Subscribe
MITRE ATT&CK · T1556

Modify Authentication Process

MITRE · cited in 6 of our lessons

Explanation

What attackers do. Attackers change authentication mechanisms, such as password filters, authentication modules, identity federation settings or MFA configuration, to capture credentials or let themselves log in without proper checks. This serves Credential Access, Defence Evasion and Persistence.

How to defend. Protect identity infrastructure as tier zero, restrict and audit changes to federation trust, authentication policies and MFA registration. Monitor for new password filters, pluggable authentication modules and changes to identity provider settings.

Signs to look for. Look for new or changed authentication components on domain controllers or servers, added federation domains or signing certificates, MFA methods registered from unusual locations and authentication succeeding without expected checks. A common gap is that identity configuration changes are not routed to the security team.

Open the technique on MITRE ATT&CK
The official text
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. 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.

© The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation (MITRE ATT&CK®).

Lessons that cite it

Real incidents where this item mattered.