T1110.001 Password Guessing

Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts. Without knowledge of the password for an account, an adversary may opt to systematically guess the password using a repetitive or iterative mechanism. An adversary may guess login credentials without prior knowledge of system or environment passwords during an operation by using a list of common passwords. Password guessing may or may not take into account the target's policies on password complexity or use policies that may lock accounts out after a number of failed attempts.

Guessing passwords can be a risky option because it could cause numerous authentication failures and account lockouts, depending on the organization's login failure policies. (Citation: Cylance Cleaver)

Typically, management services over commonly used ports are used when guessing passwords. Commonly targeted services include the following:

  • SSH (22/TCP)
  • Telnet (23/TCP)
  • FTP (21/TCP)
  • NetBIOS / SMB / Samba (139/TCP & 445/TCP)
  • LDAP (389/TCP)
  • Kerberos (88/TCP)
  • RDP / Terminal Services (3389/TCP)
  • HTTP/HTTP Management Services (80/TCP & 443/TCP)
  • MSSQL (1433/TCP)
  • Oracle (1521/TCP)
  • MySQL (3306/TCP)
  • VNC (5900/TCP)
  • SNMP (161/UDP and 162/TCP/UDP)

In addition to management services, adversaries may "target single sign-on (SSO) and cloud-based applications utilizing federated authentication protocols," as well as externally facing email applications, such as Office 365.(Citation: US-CERT TA18-068A 2018). Further, adversaries may abuse network device interfaces (such as wlanAPI) to brute force accessible wifi-router(s) via wireless authentication protocols.(Citation: Trend Micro Emotet 2020)

In default environments, LDAP and Kerberos connection attempts are less likely to trigger events over SMB, which creates Windows "logon failure" event ID 4625.

View in MITRE ATT&CK®

CRI Profile Mappings

Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
PR.IR-01.05 Remote access protection Mitigates T1110.001 Password Guessing
Comments
This diagnostic statement implements security controls and restrictions for remote user access to systems. Remote user access control involves managing and securing how users remotely access systems, such as through encrypted connections and account use policies, which help prevent adversary access.
References
    PR.AA-05.04 Third-party access management Mitigates T1110.001 Password Guessing
    Comments
    This diagnostic statement includes implementation of controls for third-party access to an organization’s systems. Enforcing third-party account use policies to include account lockout policies after a certain number of failed login attempts mitigates the risk of brute-force attacks.
    References
      PR.AA-05.02 Privileged system access Mitigates T1110.001 Password Guessing
      Comments
      This diagnostic statement protects against Password Guessing through the use of privileged account management and the use of multi-factor authentication.
      References
        PR.AA-02.01 Authentication of identity Mitigates T1110.001 Password Guessing
        Comments
        This diagnostic statement provides protection from Brute Force through the implementation of authentication controls and privileged account management controls to limit credential access. Employing limitations to specific accounts, access control mechanisms, and auditing the attribution logs provides protection against adversaries attempting to brute force credentials.
        References
          PR.PS-01.07 Cryptographic keys and certificates Mitigates T1110.001 Password Guessing
          Comments
          This diagnostic statement protects against Brute Force through the use of revocation of keys and key management. Employing strong encryption keys and limitations to specific accounts along with access control mechanisms provides protection against adversaries attempting to guess credentials.
          References
            PR.AA-03.01 Authentication requirements Mitigates T1110.001 Password Guessing
            Comments
            This diagnostic statement describes how the organization implement appropriate authentication requirements, including selecting mechanisms based on risk, utilizing multi-factor authentication where necessary, and safeguarding the storage of authenticators like pins and passwords to protect sensitive access credentials.
            References
              PR.AA-01.01 Identity and credential management Mitigates T1110.001 Password Guessing
              Comments
              This diagnostic statement protects against Password Guessing through the use of hardened access control policies, secure defaults, password complexity requirements, multifactor authentication requirements, and removal of terminated accounts.
              References

                Azure Mappings

                Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
                advanced_threat_protection_for_azure_sql_database Advanced Threat Protection for Azure SQL Database technique_scores T1110.001 Password Guessing
                Comments
                This control may alert on repeated sign in attempts to the resource and successful logins from a suspicious location, IP address, or a user that does not commonly log in to the resource. Because this control is specific to Azure database offerings, the detection coverage is Minimal.
                References
                ai_security_recommendations Microsoft Defender for Cloud: AI Security Recommendations technique_scores T1110.001 Password Guessing
                Comments
                This control's "Authentication to Linux machines should require SSH keys" can obviate SSH Brute Force password attacks. Because this is specific to Linux, the coverage score is Minimal leading to an overall Minimal score.
                References
                alerts_for_azure_network_layer Alerts for Azure Network Layer technique_scores T1110.001 Password Guessing
                Comments
                This control can identify multiple connection attempts by external IPs, which may be indicative of Brute Force attempts, though not T1110.002, which is performed offline.
                References
                alerts_for_linux_machines Alerts for Linux Machines technique_scores T1110.001 Password Guessing
                Comments
                This control may alert on multiple successful and failed brute force attempts against SSH. There are no alerts for other methods of logging into Linux machines.
                References
                alerts_for_windows_machines Alerts for Windows Machines technique_scores T1110.001 Password Guessing
                Comments
                This control may detect successful and failed brute force attempts with logic that factors the IP, time between attempts, and other suspicious activity. The following alerts may be generated: "A logon from a malicious IP has been detected", "A logon from a malicious IP has been detected. [seen multiple times]", "Successful brute force attack", "Suspicious authentication activity".
                References
                azure_policy Azure Policy technique_scores T1110.001 Password Guessing
                Comments
                This control may provide recommendations to implement multi-factor authentication, implement password security policies, and replacing password authentication with more secure authentication methods. This control can affect Azure, Azure cloud application, and endpoint credentials.
                References
                just-in-time_vm_access Microsoft Defender for Cloud: Just-in-Time VM Access technique_scores T1110.001 Password Guessing
                Comments
                This control can be configured to completely block inbound access to selected ports until access is requested. This prevents any attempt at brute forcing a protocol, such as RDP or SSH, unless the attacker has the credentials and permissions to request such access. Even if permission has been granted to an authorized user to access the virtual machine, a list of authorized IP addresses for that access can be configured.
                References

                GCP Mappings

                Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
                advanced_protection_program Advanced Protection Program technique_scores T1110.001 Password Guessing
                Comments
                Advanced Protection Program enables the use of a security key for multi-factor authentication. This provides significant protection against Brute Force techniques attempting to gain access to accounts.
                References
                cloud_identity Cloud Identity technique_scores T1110.001 Password Guessing
                Comments
                This control may mitigate brute force attacks by enforcing multi-factor authentication, enforcing strong password policies, and rotating credentials periodically. These recommendations are IAM best practices but must be explicitly implemented by a cloud administrator.
                References
                identity_platform Identity Platform technique_scores T1110.001 Password Guessing
                Comments
                Multi-factor authentication (MFA) methods, such as SMS, can also be used to help protect user accounts from phishing attacks. MFA provides significant protection against password compromises, requiring the adversary to complete an additional authentication method before their access is permitted.
                References

                AWS Mappings

                Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
                amazon_cognito Amazon Cognito technique_scores T1110.001 Password Guessing
                Comments
                MFA can significantly reduce the impact of a password compromise, requiring the adversary to complete an additional authentication method before their access is permitted.
                References
                  amazon_guardduty Amazon GuardDuty technique_scores T1110.001 Password Guessing
                  Comments
                  Due to the detection being limited to a specific set of application protocols, its coverage is Minimal resulting in a Minimal score.
                  References
                    amazon_inspector Amazon Inspector technique_scores T1110.001 Password Guessing
                    Comments
                    The Amazon Inspector Best Practices assessment package can detect security control settings related to authentication and password policies on Linux endpoints. Specific security controls it can assess include "Disable password authentication over SSH", "Configure password maximum age", "Configure password minimum length", and "Configure password complexity" all of which impact the ability to brute force a password. This information can be used identify insecure configurations and harden the endpoints. Amazon Inspector does not directly protect against brute force attacks. Given Amazon Inspector can only assess these security controls on Linux platforms (although it also supports Windows), the coverage score is Minimal leading to an overall Minimal score.
                    References
                      aws_config AWS Config technique_scores T1110.001 Password Guessing
                      Comments
                      The following AWS Config managed rules can identify configuration problems that should be fixed in order to ensure multi-factor authentication (MFA) is enabled properly, which can significantly impede brute force authentication attempts by requiring adversaries to provide a second form of authentication even if they succeed in brute forcing a password via one of these sub-techniques: "iam-user-mfa-enabled", "mfa-enabled-for-iam-console-access", "root-account-hardware-mfa-enabled", and "root-account-mfa-enabled". The "iam-password-policy" managed rule can identify insufficient password requirements that should be fixed in order to make brute force authentication more difficult by increasing the complexity of user passwords and decreasing the amount of time before they are rotated, giving adversaries less time to brute force passwords and making it more time consuming and resource intensive to do so. This is especially important in the case of Password Cracking, since adversaries in possession of password hashes may be able to recover usable credentials more quickly and do so without generating detectable noise via invalid login attempts. All of these controls are run periodically, but implemented policies are enforced continuously once set and coverage factor is significant, resulting in an overall score of Significant.
                      References
                        aws_identity_and_access_management AWS Identity and Access Management technique_scores T1110.001 Password Guessing
                        Comments
                        This control may mitigate brute force attacks by enforcing multi-factor authentication, enforcing strong password policies, and rotating credentials periodically. These recommendations are IAM best practices but must be explicitly implemented by a cloud administrator.
                        References
                          aws_security_hub AWS Security Hub technique_scores T1110.001 Password Guessing
                          Comments
                          AWS Security Hub performs a check from the AWS Foundations CIS Benchmark that, if implemented, would help towards detecting the brute forcing of accounts. AWS Security Hub provides this detection with the following checks. 3.6 Ensure a log metric filter and alarm exist for AWS Management Console authentication failures This is scored as Minimal because it only applies to the AWS Management Console and not other access mechanisms (e.g., CLI, SDK, etc.). Furthermore, it does not detect brute-forcing methods for other components such as EC2 instances.
                          References
                            aws_single_sign-on AWS Single Sign-On technique_scores T1110.001 Password Guessing
                            Comments
                            This control may protect against brute force techniques by enabling multi-factor authentication. All accounts that can be replace with single sign-on can benefit from a unified multi-factor authentication requirement.
                            References