T1550 Use Alternate Authentication Material

High-Level Description

Adversaries may use alternate authentication material, such as password hashes, Kerberos tickets, and application access tokens, in order to move laterally within an environment and bypass normal system access controls.

Authentication processes generally require a valid identity (e.g., username) along with one or more authentication factors (e.g., password, pin, physical smart card, token generator, etc.). Alternate authentication material is legitimately generated by systems after a user or application successfully authenticates by providing a valid identity and the required authentication factor(s). Alternate authentication material may also be generated during the identity creation process.

Caching alternate authentication material allows the system to verify an identity has successfully authenticated without asking the user to reenter authentication factor(s). Because the alternate authentication must be maintained by the system—either in memory or on disk—it may be at risk of being stolen through Credential Access techniques. By stealing alternate authentication material, adversaries are able to bypass system access controls and authenticate to systems without knowing the plaintext password or any additional authentication factors.

Kill Chain Phase

• Defense Evasion (TA0005)
• Lateral Movement (TA0008)

Platforms: Windows, SaaS, IaaS, Containers, Identity Provider, Office Suite, Linux

What to Check

• ] Identify if Use Alternate Authentication Material technique is applicable to target environment
• ] Check Windows systems for indicators of Use Alternate Authentication Material
• ] Check SaaS systems for indicators of Use Alternate Authentication Material
• ] Check IaaS systems for indicators of Use Alternate Authentication Material
• ] Verify mitigations are bypassed or absent (7 known mitigations)
• ] Assess detection coverage (1 detection strategies)

How to Test

Manual Testing

1. Identify Attack Surface: Determine if the target environment is susceptible to Use Alternate Authentication Material by examining the target platforms (Windows, SaaS, IaaS).

1. Assess Existing Defenses: Review whether mitigations for T1550 are in place. If defenses are absent or misconfigured, this technique may be exploitable.

1. Execute Test: Use tools and methods described in the MITRE ATT&CK page and external references below.

> Note: No Atomic Red Team tests available for this technique. See Atomic Red Team GitHub for updates.

Remediation Guide

M1047 Audit

Perform audits or scans of systems, permissions, insecure software, insecure configurations, etc. to identify potential weaknesses.

M1027 Password Policies

Set and enforce secure password policies for accounts.

M1036 Account Use Policies

Where possible, consider restricting the use of authentication material outside of expected contexts.

M1026 Privileged Account Management

Limit credential overlap across systems to prevent the damage of credential compromise and reduce the adversary's ability to perform Lateral Movement between systems.

M1015 Active Directory Configuration

Configure Active Directory to prevent use of certain techniques; use SID Filtering, etc.

M1013 Application Developer Guidance

Consider implementing token binding strategies, such as Azure AD token protection or OAuth Proof of Possession, that cryptographically bind a token to a secret. This may prevent the token from being used without knowledge of the secret or possession of the device the token is tied to.

M1018 User Account Management

Enforce the principle of least-privilege. Do not allow a domain user to be in the local administrator group on multiple systems.

Detection

Behavioral Detection Strategy for Use Alternate Authentication Material (T1550)

Risk Assessment

| Finding | Severity | Impact | | ---------------------------------------------------------- | -------- | --------------- | | Use Alternate Authentication Material technique applicable | High | Defense Evasion |

CWE Categories

| CWE ID | Title | | ------- | ---------------------------- | | CWE-693 | Protection Mechanism Failure |

References

• TechNet Audit Policy
• NIST Authentication
• NIST MFA
• Atomic Red Team - T1550
• MITRE ATT&CK - T1550