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.
| ID | Name | Description |
|---|---|---|
| S0377 | Ebury |
Ebury can intercept private keys using a trojanized |
| G1016 | FIN13 |
FIN13 has replaced legitimate KeePass binaries with trojanized versions to collect passwords from numerous applications.[2] |
| S0487 | Kessel |
Kessel has trojanized the |
| S0692 | SILENTTRINITY |
SILENTTRINITY can create a backdoor in KeePass using a malicious config file and in TortoiseSVN using a registry hook.[4] |
| ID | Mitigation | Description |
|---|---|---|
| M1047 | Audit |
Review authentication logs to ensure that mechanisms such as enforcement of MFA are functioning as intended. Periodically review the hybrid identity solution in use for any discrepancies. For example, review all Pass Through Authentication (PTA) agents in the Azure Management Portal to identify any unwanted or unapproved ones.[5] If ADFS is in use, review DLLs and executable files in the AD FS and Global Assembly Cache directories to ensure that they are signed by Microsoft. Note that in some cases binaries may be catalog-signed, which may cause the file to appear unsigned when viewing file properties.[6] Periodically review for new and unknown network provider DLLs within the Registry ( |
| M1032 | Multi-factor Authentication |
Integrating multi-factor authentication (MFA) as part of organizational policy can greatly reduce the risk of an adversary gaining control of valid credentials that may be used for additional tactics such as initial access, lateral movement, and collecting information. MFA can also be used to restrict access to cloud resources and APIs. |
| M1028 | Operating System Configuration |
Ensure only valid password filters are registered. Filter DLLs must be present in Windows installation directory ( Starting in Windows 11 22H2, the |
| M1027 | Password Policies |
Ensure that |
| M1026 | Privileged Account Management |
Audit domain and local accounts as well as their permission levels routinely to look for situations that could allow an adversary to gain wide access by obtaining credentials of a privileged account. [9] [10] These audits should also include if default accounts have been enabled, or if new local accounts are created that have not be authorized. Follow best practices for design and administration of an enterprise network to limit privileged account use across administrative tiers. [11] Limit access to the root account and prevent users from modifying protected components through proper privilege separation (ex SELinux, grsecurity, AppArmor, etc.) and limiting Privilege Escalation opportunities. Limit on-premises accounts with access to the hybrid identity solution in place. For example, limit Azure AD Global Administrator accounts to only those required, and ensure that these are dedicated cloud-only accounts rather than hybrid ones.[6] |
| M1025 | Privileged Process Integrity |
Enabled features, such as Protected Process Light (PPL), for LSA.[12] |
| M1022 | Restrict File and Directory Permissions |
Restrict write access to the |
| M1024 | Restrict Registry Permissions |
Restrict Registry permissions to disallow the modification of sensitive Registry keys such as |
| M1018 | User Account Management |
Ensure that proper policies are implemented to dictate the the secure enrollment and deactivation of authentication mechanisms, such as MFA, for user accounts. |
| ID | Data Source | Data Component | Detects |
|---|---|---|---|
| DS0026 | Active Directory | Active Directory Object Modification |
Monitor for changes made to AD security settings related to MFA logon requirements, such as changes to Azure AD Conditional Access Policies or the registration of new MFA applications. Monitor for changes made to security settings related to Azure AD Conditional Access Policies. These can be found in the Azure AD audit log under the operation name Analytic 1 - Changes to AD security settings outside of normal maintenance windows.
|
| DS0015 | Application Log | Application Log Content |
Enable security auditing to collect logs from hybrid identity solutions. For example, monitor sign-ins to the Entra ID Application Proxy Connector, which are typically generated only when a new Pass Through Authentication (PTA) Agent is added. [5] If AD FS is in use, review the logs for event ID 501, which specifies all EKU attributes on a claim, and raise alerts on any values that are not configured in your environment.[6] Analytic 1 - Unexpected sign-ins or new PTA Agent additions.
|
| DS0025 | Cloud Service | Cloud Service Modification |
Monitor for changes made to conditional access policies used by SaaS identity providers and internal IaaS identity and access management systems. Analytic 1 - Changes to access policies without corresponding change requests.
|
| DS0022 | File | File Creation |
Monitor for suspicious additions to the Monitor for newly created files that may be used to register malicious network provider dynamic link libraries (DLLs). Analytic 1 - Unauthorized file creation in critical directories.
|
| File Modification |
Monitor for suspicious modification of files associated with authentication processes, such as configuration files and module paths (e.g. Analytic 1 - Unauthorized modifications to authentication-related files.
|
||
| DS0028 | Logon Session | Logon Session Creation |
Monitor for newly constructed logon behavior across systems that share accounts, either user, admin, or service accounts. Examples: one account logged into multiple systems simultaneously; multiple accounts logged into the same machine simultaneously; accounts logged in at odd times (ex: when the user is not present) or outside of business hours. Activity may be from interactive login sessions or process ownership from accounts being used to execute binaries on a remote system as a particular account. Correlate other security systems with login information (e.g., a user has an active login session but has not entered the building or does not have VPN access). Configure robust, consistent account activity audit policies across the enterprise and with externally accessible services.[15] Analytic 1 - Unusual logon patterns and times.
|
| DS0011 | Module | Module Load |
Monitor for new, unfamiliar DLL files written to a domain controller and/or local computer. Password filters will also show up as an autorun and loaded DLL in lsass.exe.[16] If AD FS is in use, monitor the AD FS server for the creation of DLLs as well as the loading of unrecognized or unsigned DLLs into the Analytic 1 - Unauthorized DLL loads in critical systems.
|
| DS0009 | Process | OS API Execution |
Monitor for calls to Monitor for abnormal API calls to Analytic 1 - Unauthorized API calls to manipulate lsass.exe or abnormal API calls
Analytic 2 - Unauthorized API calls to manipulate lsass.exe or abnormal API calls to NPLogonNotify().
|
| Process Access |
Monitor for unexpected processes interacting with authentication mechanisms and processes to access user credentials or enable otherwise unwarranted access to accounts. Analytic 1 - Unauthorized process interactions with authentication mechanisms.
|
||
| DS0002 | User Account | User Account Authentication |
Monitor for account authentications in which MFA credentials are not provided by the user account to the authenticating entity. Analytic 1 - Windows Successful logons without MFA.
Analytic 2 - Linux Successful logons without MFA.
|
| User Account Modification |
Monitor for the enrollment of devices and user accounts with alternative security settings that do not require MFA credentials for successful logon. Analytic 1 - Unauthorized modification of user accounts Windows (User Account Modification)
Analytic 2 - macOS/Linux (User Account Modification)
|
||
| DS0024 | Windows Registry | Windows Registry Key Creation |
Monitor for the addition of network provider Registry keys (e.g., Analytic 1 - Unauthorized addition of network provider Registry keys.
|
| Windows Registry Key Modification |
Monitor for changes to Registry entries for password filters (ex: Monitor for changes to Registry entries for network providers (e.g., Analytic 1 - Unauthorized modifications to Registry entries for password filters or network providers.
Analytic 2 - Unauthorized modification of windows Registry keys may modify authentication mechanism
|