T1548: Abuse Elevation Control Mechanism
Adversaries may circumvent mechanisms designed to control elevate privileges to gain higher-level permissions. Most modern systems contain native elevation control mechanisms that are intended to limit privileges that a user can perform on a machine. Authorization has to be granted to specific users in order to perform tasks that can be considered of higher risk. An adversary can perform several methods to take advantage of built-in control mechanisms in order to escalate privileges on a system.
Positive Technologies products that cover the technique
MaxPatrol SIEM knowledge base
pt_nad: PT-CR-737: NAD_SAM_account_name_spoofing: A user requested a TGT
unix_mitre_attck_privilege_escalation: PT-CR-1663: Unix_Privilege_Escalation_via_GTFOBINS: An elevated terminal was launched using a GTFOBins utility. GTFOBins is a Unix binaries that can be used to bypass local security restrictions in misconfigured systems.
sap_suspicious_user_activity: PT-CR-234: SAPASABAP_Debug_mode_usage: A user started the debug mode
sap_suspicious_user_activity: PT-CR-235: SAPASABAP_Development_transaction_usage: A development transaction is started
sap_suspicious_user_activity: PT-CR-251: SAPASABAP_Start_critical_report: Run of SAP critical report
active_directory_attacks: PT-CR-654: SAM_Account_Name_Spoofing: The user renamed the AD object or requested a TGT ticket on behalf of an account that matches the name of the domain controller. This may indicate a sAMAccountName spoofing attack. It can allow an attacker to obtain a TGT ticket, for example, in the name of a domain controller, gain a foothold in the system and increase their privileges
active_directory_attacks: PT-CR-831: Computer_Delegation_Configured: One of the types of delegation is configured in the domain: unlimited delegation, limited delegation, limited resource-based delegation. An attacker can use this setting to obtain users TGT or TGS tickets. After that, an attacker can elevate privileges and horizontally move to other infrastructure nodes
Detection
ID | DS0002 | Data source and component | User Account: User Account Modification | Description | Log cloud API calls to assume, create, or impersonate additional roles, policies, and permissions. Review uses of just-in-time access to ensure that any justifications provided are valid and only expected actions were taken. |
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ID | DS0009 | Data source and component | Process: Process Metadata | Description | Monitor contextual data about a running process, which may include information such as environment variables, image name, user/owner that may circumvent mechanisms designed to control elevate privileges to gain higher-level permissions. |
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ID | DS0009 | Data source and component | Process: Process Creation | Description | Monitor for newly executed processes that may circumvent mechanisms designed to control elevate privileges to gain higher-level permissions. Cyber actors frequently escalate to the SYSTEM account after gaining entry to a Windows host, to enable them to carry out various attacks more effectively. Tools such as Meterpreter, Cobalt Strike, and Empire carry out automated steps to “Get System”, which is the same as switching over to the System user account. Most of these tools utilize multiple techniques to try and attain SYSTEM: in the first technique, they create a named pipe and connects an instance of cmd.exe to it, which allows them to impersonate the security context of cmd.exe, which is SYSTEM. In the second technique, a malicious DLL is injected into a process that is running as SYSTEM; the injected DLL steals the SYSTEM token and applies it where necessary to escalate privileges. This analytic looks for both of these techniques. Analytic 1 - Get System Elevation
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ID | DS0009 | Data source and component | Process: OS API Execution | Description | Also look for any process API calls for behavior that may be indicative of Process Injection. Monitoring OS API callbacks for the execution can also be a way to detect this behavior but requires specialized security tooling. |
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ID | DS0024 | Data source and component | Windows Registry: Windows Registry Key Modification | Description | There are many ways to perform UAC bypasses when a user is in the local administrator group on a system, so it may be difficult to target detection on all variations. Efforts should likely be placed on mitigation and collecting enough information on process launches and actions that could be performed before and after a UAC bypass is performed. Some UAC bypass methods rely on modifying specific, user-accessible Registry settings. Analysts should monitor Registry settings for unauthorized changes. |
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ID | DS0017 | Data source and component | Command: Command Execution | Description | Monitor executed commands and arguments that may circumvent mechanisms designed to control elevate privileges to gain higher-level permissions. |
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ID | DS0022 | Data source and component | File: File Modification | Description | On Linux, auditd can alert every time a user's actual ID and effective ID are different (this is what happens when you sudo). This technique is abusing normal functionality in macOS and Linux systems, but sudo has the ability to log all input and output based on the |
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ID | DS0022 | Data source and component | File: File Metadata | Description | Monitor the file system for files that have the setuid or setgid bits set. On Linux, auditd can alert every time a user's actual ID and effective ID are different (this is what happens when you sudo). |
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Mitigation
ID | M1038 | Name | Execution Prevention | Description | System settings can prevent applications from running that haven't been downloaded from legitimate repositories which may help mitigate some of these issues. Not allowing unsigned applications from being run may also mitigate some risk. |
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ID | M1028 | Name | Operating System Configuration | Description | Applications with known vulnerabilities or known shell escapes should not have the setuid or setgid bits set to reduce potential damage if an application is compromised. Additionally, the number of programs with setuid or setgid bits set should be minimized across a system. Ensuring that the sudo tty_tickets setting is enabled will prevent this leakage across tty sessions. |
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ID | M1051 | Name | Update Software | Description | Perform regular software updates to mitigate exploitation risk. |
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ID | M1052 | Name | User Account Control | Description | Although UAC bypass techniques exist, it is still prudent to use the highest enforcement level for UAC when possible and mitigate bypass opportunities that exist with techniques such as DLL Search Order Hijacking. |
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ID | M1026 | Name | Privileged Account Management | Description | Remove users from the local administrator group on systems. By requiring a password, even if an adversary can get terminal access, they must know the password to run anything in the sudoers file. Setting the timestamp_timeout to 0 will require the user to input their password every time sudo is executed. |
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ID | M1018 | Name | User Account Management | Description | Limit the privileges of cloud accounts to assume, create, or impersonate additional roles, policies, and permissions to only those required. Where just-in-time access is enabled, consider requiring manual approval for temporary elevation of privileges. |
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ID | M1047 | Name | Audit | Description | Check for common UAC bypass weaknesses on Windows systems to be aware of the risk posture and address issues where appropriate. |
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ID | M1022 | Name | Restrict File and Directory Permissions | Description | The sudoers file should be strictly edited such that passwords are always required and that users can't spawn risky processes as users with higher privilege. |
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