Query: Outbound C2 pattern associated with Additional Email Delegate Permissions
Matching passage: T1098.002 Additional Email Delegate Permissions. Tactics: persistence, privilege escalation. Description: Adversaries may grant additional permission levels to maintain persistent access to an adversary-controlled email account. For example, the <code>Add-MailboxPermission</code> [PowerShell](https://attack.mitre.org/techniques/T1059/001) cmdlet, available in on-premises Exchange and in the cloud-based service Office 365, adds permissions to a mailbox.(Citation: Microsoft - Add-MailboxPermission)(Citation: FireEye APT35 2018)(Citation: Crowdstrike Hiding in Plain Sight 2018) In Google Workspace, delegation can be enabled via the Google Admin console and users can delegate accounts via their Gmail settings.(Citation: Gmail Delegation)(Citation: Google Ensuring Your Information is Safe) Adversaries may also assign mailbox folder permissions through individual folder permissions or roles. In Office 365 environments, adversaries may assign the Default or Anonymous user permissions or roles to the Top of Information Store (root), Inbox, or other mailbox folders. By assigning one or both user permissions to a folder, the adversary can utilize any other account in the tenant to maintain persistence to the target user’s mail folders.(Citation: Mandiant Defend UNC2452 White Paper) This may be used in persistent threat incidents as well as BEC (Business Email Compromise) incidents where an adversary can add [Additional Cloud Roles](https://attack.mitre.org/techniques/T1098/003) to the accounts they wish to compromise. This may further enable use of additional techniques for gaining access to systems. For example, compromised business accounts are often used to send messages to other accounts in the network of the target business while creating inbox rules (ex: [Internal Spearphishing](https://attack.mitre.org/techniques/T1534)), so the messages evade spam/phishing detection mechanisms.(Citation: Bienstock, D. - Defending O365 - 2019)
Near-miss passage: T1098.007 Additional Local or Domain Groups. Tactics: persistence, privilege escalation. Description: An adversary may add additional local or domain groups to an adversary-controlled account to maintain persistent access to a system or domain. On Windows, accounts may use the `net localgroup` and `net group` commands to add existing users to local and domain groups.(Citation: Microsoft Net Localgroup)(Citation: Microsoft Net Group) On Linux, adversaries may use the `usermod` command for the same purpose.(Citation: Linux Usermod) For example, accounts may be added to the local administrators group on Windows devices to maintain elevated privileges. They may also be added to the Remote Desktop Users group, which allows them to leverage [Remote Desktop Protocol](https://attack.mitre.org/techniques/T1021/001) to log into the endpoints in the future.(Citation: Microsoft RDP Logons) Adversaries may also add accounts to VPN user groups to gain future persistence on the network.(Citation: Cyber Security News) On Linux, accounts may be added to the sudoers group, allowing them to persistently leverage [Sudo and Sudo Caching](https://attack.mitre.org/techniques/T1548/003) for elevated privileges. In Windows environments, machine accounts may also be added to domain groups. This allows the local SYSTEM account to gain privileges on the domain.(Citation: RootDSE AD Detection 2022)