Query: Encoded PowerShell / command-line abuse matching Multi-Factor Authentication Request Generation
Matching passage: T1621 Multi-Factor Authentication Request Generation. Tactics: credential access. Description: Adversaries may attempt to bypass multi-factor authentication (MFA) mechanisms and gain access to accounts by generating MFA requests sent to users. Adversaries in possession of credentials to [Valid Accounts](https://attack.mitre.org/techniques/T1078) may be unable to complete the login process if they lack access to the 2FA or MFA mechanisms required as an additional credential and security control. To circumvent this, adversaries may abuse the automatic generation of push notifications to MFA services such as Duo Push, Microsoft Authenticator, Okta, or similar services to have the user grant access to their account. If adversaries lack credentials to victim accounts, they may also abuse automatic push notification generation when this option is configured for self-service password reset (SSPR).(Citation: Obsidian SSPR Abuse 2023) In some cases, adversaries may continuously repeat login attempts in order to bombard users with MFA push notifications, SMS messages, and phone calls, potentially resulting in the user finally accepting the authentication request in response to “MFA fatigue.”(Citation: Russian 2FA Push Annoyance - Cimpanu)(Citation: MFA Fatigue Attacks - PortSwigger)(Citation: Suspected Russian Activity Targeting Government and Business Entities Around the Globe)
Near-miss passage: T1003.005 Cached Domain Credentials. Tactics: credential access. Description: Adversaries may attempt to access cached domain credentials used to allow authentication to occur in the event a domain controller is unavailable.(Citation: Microsoft - Cached Creds) On Windows Vista and newer, the hash format is DCC2 (Domain Cached Credentials version 2) hash, also known as MS-Cache v2 hash.(Citation: PassLib mscache) The number of default cached credentials varies and can be altered per system. This hash does not allow pass-the-hash style attacks, and instead requires [Password Cracking](https://attack.mitre.org/techniques/T1110/002) to recover the plaintext password.(Citation: ired mscache) On Linux systems, Active Directory credentials can be accessed through caches maintained by software like System Security Services Daemon (SSSD) or Quest Authentication Services (formerly VAS). Cached credential hashes are typically located at `/var/lib/sss/db/cache.[domain].ldb` for SSSD or `/var/opt/quest/vas/authcache/vas_auth.vdb` for Quest. Adversaries can use utilities, such as `tdbdump`, on these database files to dump the cached hashes and use [Password Cracking](https://attack.mitre.org/techniques/T1110/002) to obtain the plaintext password.(Citation: Brining MimiKatz to Unix) With SYSTEM or sudo access, the tools/utilities such as [Mimikatz](https://attack.mitre.org/software/S0002), [Reg](https://attack.mitre.org/software/S0075), and secretsdump.py for Windows or Linikatz for Linux can be used to extract the cached credentials.(Citation: Brining MimiKatz to Unix) Note: Cached credentials for Windows Vista are derived using PBKDF2.(Citation: PassLib mscache)