Ensure 'Attachment Filtering Agent' is configured

高レベル 1自動exchange

説明

The attachment filtering on Edge Transport servers restricts attachments that users receive in email messages. Attachment filtering is performed by the Attachment Filtering agent, which is available only on Edge Transport servers, and is unchanged from Exchange Server 2010. Ensure the Attachment Filtering Agent is Enabled, and the extension filtering list is configured to the desired state. Prints compliant when the Attachment Filtering Agent is enabled and every extension in the benchmark reference list is present in Get-AttachmentFilterEntry (FileName entries). The list is the one printed in the benchmark; trim it for documented organizational exceptions. Run on each Edge Transport server. Run from an Exchange Management Shell or after `Add-PSSnapin Microsoft.Exchange.Management.PowerShell.SnapIn`; the audit loads the snap-in itself when Get-ExchangeServer is missing and fails if it cannot.

チェック方法

監査方法: シェルコマンド

shell

$ErrorActionPreference = 'Stop'; if (-not (Get-Command Get-ExchangeServer -ErrorAction SilentlyContinue)) { Add-PSSnapin Microsoft.Exchange.Management.PowerShell.SnapIn -ErrorAction Stop }; if (-not (Get-Command Get-ExchangeServer -ErrorAction SilentlyContinue)) { throw 'Exchange Management Shell cmdlets are not available' }; $a = Get-TransportAgent 'Attachment Filtering Agent' -ErrorAction Stop; $names = @(Get-AttachmentFilterEntry -ErrorAction Stop | ForEach-Object { "$($_.Name)".ToLowerInvariant() }); $want = @('*.ace','*.ade','*.adp','*.ani','*.app','*.appx','*.arj','*.asx','*.bas','*.bat','*.cab','*.chm','*.cmd','*.com','*.cpl','*.crt','*.csh','*.dbf','*.dcr','*.deb','*.dex','*.dif','*.dir','*.dll','*.doc','*.dot','*.docm','*.elf','*.exe','*.fxp','*.hlp','*.hta','*.htc','*.htm','*.html','*.img','*.inf','*.ins','*.iso','*.isp','*.jar','*.jnlp','*.js','*.jse','*.kext','*.ksh','*.lha','*.lib','*.lnk','*.lzh','*.macho','*.mda','*.mdb','*.mde','*.mdt','*.mdw','*.mdz','*.mht','*.mhtml','*.msc','*.msi','*.msix','*.msp','*.mst','*.ops','*.pcd','*.pif','*.plg','*.ppa','*.ppt','*.ppam','*.prf','*.prg','*.ps1','*.ps11','*.ps11xml','*.ps1xml','*.ps2','*.ps2xml','*.psc1','*.psc2','*.reg','*.rev','*.scf','*.scr','*.sct','*.shb','*.shs','*.shtm','*.shtml','*.slk','*.spl','*.stm','*.swf','*.sys','*.uif','*.url','*.vb','*.vbe','*.vbs','*.vxd','*.wsc','*.wsf','*.wsh','*.xlam','*.xla','*.xlc','*.xll','*.xls','*.xlsm','*.xlt','*.xlw','*.xml','*.xnk','*.xz','*.z'); $missing = @($want | Where-Object { $names -notcontains $_ }); if ($a.Enabled -eq $true -and $missing.Count -eq 0) { 'compliant' } else { 'noncompliant' }

期待される出力: compliant

修正方法

修正方法: ガイダンスまたは IaC パッチ

Enable-TransportAgent 'Attachment Filtering Agent'; then add each missing extension from the benchmark list: foreach ($e in @('*.ace','*.ade',...)) { Add-AttachmentFilterEntry -Name $e -Type FileName -ErrorAction SilentlyContinue }

プロパティ

オペレーティングシステム: すべて
タグ: exchangemalware
参照: CIS Microsoft Exchange Server 2019 Benchmark v1.0.1 - 1.8 Ensure 'Attachment Filtering Agent' is configured

このホストをチェック

監査が許可されているマシンで実行してください。スキャンは読み取り専用です。

shell

tmaegis scan --target exchange