Query: EDR alert: possible Pass the Hash (T1550.002)
Matching passage: T1550.002 Pass the Hash. Tactics: lateral movement. Description: Adversaries may “pass the hash” using stolen password hashes to move laterally within an environment, bypassing normal system access controls. Pass the hash (PtH) is a method of authenticating as a user without having access to the user's cleartext password. This method bypasses standard authentication steps that require a cleartext password, moving directly into the portion of the authentication that uses the password hash. When performing PtH, valid password hashes for the account being used are captured using a [Credential Access](https://attack.mitre.org/tactics/TA0006) technique. Captured hashes are used with PtH to authenticate as that user. Once authenticated, PtH may be used to perform actions on local or remote systems. Adversaries may also use stolen password hashes to "overpass the hash." Similar to PtH, this involves using a password hash to authenticate as a user but also uses the password hash to create a valid Kerberos ticket. This ticket can then be used to perform [Pass the Ticket](https://attack.mitre.org/techniques/T1550/003) attacks.(Citation: Stealthbits Overpass-the-Hash)
Near-miss passage: T1550.001 Application Access Token. Tactics: lateral movement. Description: Adversaries may use stolen application access tokens to bypass the typical authentication process and access restricted accounts, information, or services on remote systems. These tokens are typically stolen from users or services and used in lieu of login credentials. Application access tokens are used to make authorized API requests on behalf of a user or service and are commonly used to access resources in cloud, container-based applications, and software-as-a-service (SaaS).(Citation: Auth0 - Why You Should Always Use Access Tokens to Secure APIs Sept 2019) OAuth is one commonly implemented framework that issues tokens to users for access to systems. These frameworks are used collaboratively to verify the user and determine what actions the user is allowed to perform. Once identity is established, the token allows actions to be authorized, without passing the actual credentials of the user. Therefore, compromise of the token can grant the adversary access to resources of other sites through a malicious application.(Citation: okta) For example, with a cloud-based email service, once an OAuth access token is granted to a malicious application, it can potentially gain long-term access to features of the user account if a "refresh" token enabling background access is awarded.(Citation: Microsoft Identity Platform Access 2019) With an OAuth access token an adversary can use the user-granted REST API to perform functions such as email searching and contact enumeration.(Citation: Staaldraad Phishing with OAuth 2017) Compromised access tokens may be used as an initial step in compromising other services. For example, if a token grants access to a victim’s primary email, the adversary may be able to extend access to all other services which the target subscribes by triggering forgotten password routines. In AWS and GCP environments, adversaries can trigger a request for a short-lived access token with the privileges of another user account.(Citation: Google Cloud Service