New-SafeAttachmentPolicy

This cmdlet is available only in the cloud-based service.

Use the New-SafeAttachmentPolicy cmdlet to create safe attachment policies in your cloud-based organization.

For information about the parameter sets in the Syntax section below, see Exchange cmdlet syntax.

Syntax

New-SafeAttachmentPolicy
   [-Name] <String>
   [-Action <SafeAttachmentAction>]
   [-AdminDisplayName <String>]
   [-Confirm]
   [-Enable <Boolean>]
   [-MakeBuiltInProtection]
   [-QuarantineTag <String>]
   [-RecommendedPolicyType <RecommendedPolicyType>]
   [-Redirect <Boolean>]
   [-RedirectAddress <SmtpAddress>]
   [-WhatIf]
   [<CommonParameters>]

Description

Safe Attachments is a feature in Microsoft Defender for Office 365 that opens email attachments in a special hypervisor environment to detect malicious activity. For more information, see Safe Attachments in Defender for Office 365.

New safe attachment policies that you create using this cmdlet aren't applied to users and aren't visible in the Microsoft Defender portal. You need to use the SafeAttachmentPolicy parameter on the New-SafeAttachmentRule or Set-SafeAttachmentRule cmdlets to associate the policy with a rule to create a complete Safe Attachments policy that's visible in the Defender portal.

A safe attachment policy can be assigned to only one safe attachment rule.

You need to be assigned permissions before you can run this cmdlet. Although this topic lists all parameters for the cmdlet, you may not have access to some parameters if they're not included in the permissions assigned to you. To find the permissions required to run any cmdlet or parameter in your organization, see Find the permissions required to run any Exchange cmdlet.

Examples

Example 1

New-SafeAttachmentPolicy -Name "Marketing Block Attachments" -Enable $true -Redirect $true -RedirectAddress admin@contoso.com

This example creates a new safe attachment policy named Marketing Block Attachments with the following options:

  • The action is Block. This is the default value of the Action parameter, so you don't need to specify it.
  • The value $true for the Enable parameter is required so the policy will actually use the default Action parameter value of Block (or any other Action parameter value).
  • Enable redirection for detected malware attachments and send the messages to admin@contoso.com.
  • If Safe Attachments scanning isn't available or encounters errors, don't deliver the message as normal. The default value of the ActionOnError parameter is $true, so you don't need to specify it.

Parameters

-Action

The Action parameter specifies the action for the safe attachment policy. Valid values are:

  • Allow: Deliver the message if malware is detected in the attachment and track scanning results. This value corresponds to Monitor for the Safe Attachments unknown malware response property of the policy in the Microsoft Defender portal.
  • Block: Block the email message that contains the malware attachment. This is the default value.
  • DynamicDelivery: Deliver the email message with a placeholder for each email attachment. The placeholder remains until a copy of the attachment is scanned and determined to be safe. For more information, see Dynamic Delivery in Safe Attachments policies.

The value of this parameter is meaningful only when the value of the Enable parameter is $true (the default value is $false).

To specify no action for the safe attachment policy (corresponds to the value Off for the Safe Attachments unknown malware response policy setting in the Defender portal), use the value $false for the Enable parameter.

The results of all actions are available in message trace.

Type:SafeAttachmentAction
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-AdminDisplayName

The AdminDisplayName parameter specifies a description for the policy. If the value contains spaces, enclose the value in quotation marks (").

Type:String
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-Confirm

The Confirm switch specifies whether to show or hide the confirmation prompt. How this switch affects the cmdlet depends on if the cmdlet requires confirmation before proceeding.

  • Destructive cmdlets (for example, Remove-* cmdlets) have a built-in pause that forces you to acknowledge the command before proceeding. For these cmdlets, you can skip the confirmation prompt by using this exact syntax: -Confirm:$false.
  • Most other cmdlets (for example, New-* and Set-* cmdlets) don't have a built-in pause. For these cmdlets, specifying the Confirm switch without a value introduces a pause that forces you acknowledge the command before proceeding.
Type:SwitchParameter
Aliases:cf
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-Enable

The Enable parameter works with the Action parameter to specify the action for the safe attachment policy. Valid values are:

  • $true: The Action parameter specifies the action for the Safe Attachment policy.
  • $false: This is the default value. Attachments are not scanned by Safe Attachments, regardless of the value of the Action parameter. This value corresponds to the Off selection for the Safe Attachments unknown malware response setting of the policy in the Microsoft Defender portal.

To enable or disable a complete Safe Attachments policy in the Microsoft Defender portal (the combination of the rule and the corresponding associated policy in PowerShell), use the Enable-SafeAttachmentRule or Disable-SafeAttachmentRule cmdlets.

Type:Boolean
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-MakeBuiltInProtection

The MakeBuiltInProtection switch is used for Built-in protection policy creation as part of Preset security policies. Don't use this switch yourself.

Type:SwitchParameter
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-Name

The Name parameter specifies a unique name for the safe attachment policy. If the value contains spaces, enclose the value in quotation marks (").

Type:String
Position:1
Default value:None
Required:True
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-QuarantineTag

The QuarantineTag parameter specifies the quarantine policy that's used on messages that are quarantined as malware by Safe Attachments. You can use any value that uniquely identifies the quarantine policy. For example:

  • Name
  • Distinguished name (DN)
  • GUID

Quarantine policies define what users are able to do to quarantined messages based on why the message was quarantined and quarantine notification settings. For more information about quarantine policies, see Quarantine policies.

If you don't use this parameter, the built-in quarantine policy named AdminOnlyAccessPolicy is used. This quarantine policy enforces the historical capabilities for messages that were quarantined as malware by Safe Attachments as described in the table here.

To view the list of available quarantine policies, run the following command: Get-QuarantinePolicy | Format-List Name,EndUser*,ESNEnabled.

Type:String
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-RecommendedPolicyType

The RecommendedPolicyType parameter is used for Standard and Strict policy creation as part of Preset security policies. Don't use this parameter yourself.

Type:RecommendedPolicyType
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-Redirect

The Redirect parameter specifies whether to deliver messages to an alternate email address if malware is detected in an attachment. Valid values are:

  • $true: Messages that contain malware attachments are delivered to the email address specified by the RedirectAddress parameter. This value is meaningful only when the value of the Action parameter is Allow.
  • $false: Messages that contain malware attachments aren't delivered to another email address. This is the default value.
Type:Boolean
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-RedirectAddress

The RedirectAddress parameter specifies the destination email address to deliver messages if malware is detected in an attachment.

The value of this parameter is meaningful only when value of the Redirect parameter is $true and the value of the Action parameter is Allow.

Type:SmtpAddress
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online

-WhatIf

The WhatIf switch simulates the actions of the command. You can use this switch to view the changes that would occur without actually applying those changes. You don't need to specify a value with this switch.

Type:SwitchParameter
Aliases:wi
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False
Applies to:Exchange Online