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Merged
merill merged 3 commits into from
Aug 1, 2026
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Merged

fix(exchange): handle missing DKIM signing configurations #2001

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3d9aece
fix(tests): resolve missing DKIM config exceptions
amlhive-tech Jul 25, 2026
1a2489f
fix: identify initial domain for automatic DKIM
merill Aug 1, 2026
ad04a26
test: cover missing DKIM configuration outcomes
merill Aug 1, 2026
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11 changes: 11 additions & 0 deletions powershell/public/cis/Test-MtCisDkim.ps1
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Original file line number Diff line number Diff line change
Expand Up @@ -42,6 +42,17 @@
$_.domain -eq $domain.domainname
}

if (-not $dkimSigningConfig) {
$dkimRecord = [PSCustomObject]@{
domain = $domain.DomainName
pass = if ($domain.SendingFromDomainDisabled) { 'Skipped' } elseif ($domain.InitialDomain -eq $true) { 'Passed' } else { 'Failed' }
reason = if ($domain.SendingFromDomainDisabled) { 'Parked domain' } elseif ($domain.InitialDomain -eq $true) { 'Microsoft auto-signs DKIM for the initial onmicrosoft.com domain' } else { 'No DkimSigningConfig found for domain' }
dkimRecord = $null
}
$dkimRecords += $dkimRecord
continue
}

if ((Get-Date) -gt $dkimSigningConfig.RotateOnDate) {
if ($Selector -ne $dkimSigningConfig.SelectorAfterRotateOnDate) {
Write-Verbose "Using DKIM $($dkimSigningConfig.SelectorAfterRotateOnDate) based on EXO config"
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11 changes: 11 additions & 0 deletions powershell/public/cisa/exchange/Test-MtCisaDkim.ps1
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Original file line number Diff line number Diff line change
Expand Up @@ -40,6 +40,17 @@
$dkimSigningConfig = $dkimSigningConfigs | Where-Object {`
$_.domain -eq $domain.domainname
}

if (-not $dkimSigningConfig) {
$dkimRecord = [PSCustomObject]@{
domain = $domain.DomainName
pass = if ($domain.SendingFromDomainDisabled) { 'Skipped' } elseif ($domain.InitialDomain -eq $true) { 'Passed' } else { 'Failed' }
reason = if ($domain.SendingFromDomainDisabled) { 'Parked domain' } elseif ($domain.InitialDomain -eq $true) { 'Microsoft auto-signs DKIM for the initial onmicrosoft.com domain' } else { 'No DkimSigningConfig found for domain' }
dkimRecord = $null
}
$dkimRecords += $dkimRecord
continue
}
if ((Get-Date) -gt $dkimSigningConfig.RotateOnDate) {
if ($Selector -ne $dkimSigningConfig.SelectorAfterRotateOnDate) {
Write-Verbose "Using DKIM $($dkimSigningConfig.SelectorAfterRotateOnDate) based on EXO config"
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88 changes: 88 additions & 0 deletions powershell/tests/functions/Test-MtDkim.Tests.ps1
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Original file line number Diff line number Diff line change
@@ -0,0 +1,88 @@
BeforeAll {
Import-Module "$PSScriptRoot/../../Maester.psd1" -Force
}

Describe 'DKIM checks with no signing configuration' -ForEach @(
@{ CommandName = 'Test-MtCisDkim' }
@{ CommandName = 'Test-MtCisaDkim' }
) {
BeforeEach {
Mock -ModuleName Maester Test-MtConnection { return $true }
Mock -ModuleName Maester Add-MtTestResultDetail { }
Mock -ModuleName Maester Get-MailAuthenticationRecord {
throw 'DNS lookup should not be attempted without a DKIM signing configuration'
}
}

It '<CommandName> returns <ExpectedOutcome> for <DomainName>' -ForEach @(
@{
DomainName = 'contoso.onmicrosoft.com'
InitialDomain = $true
IsCoexistenceDomain = $false
SendingFromDomainDisabled = $false
ExpectedOutcome = 'passed'
ExpectedResult = $true
}
@{
DomainName = 'secondary.onmicrosoft.com'
InitialDomain = $false
IsCoexistenceDomain = $false
SendingFromDomainDisabled = $false
ExpectedOutcome = 'failed'
ExpectedResult = $false
}
@{
DomainName = 'parked.example'
InitialDomain = $false
IsCoexistenceDomain = $false
SendingFromDomainDisabled = $true
ExpectedOutcome = 'skipped'
ExpectedResult = $null
}
@{
DomainName = 'contoso.mail.onmicrosoft.com'
InitialDomain = $false
IsCoexistenceDomain = $true
SendingFromDomainDisabled = $false
ExpectedOutcome = 'failed'
ExpectedResult = $false
}
@{
DomainName = 'contoso.mail.onmicrosoft.com'
InitialDomain = $false
IsCoexistenceDomain = $true
SendingFromDomainDisabled = $true
ExpectedOutcome = 'skipped'
ExpectedResult = $null
}
@{
DomainName = 'contoso.com'
InitialDomain = $false
IsCoexistenceDomain = $false
SendingFromDomainDisabled = $false
ExpectedOutcome = 'failed'
ExpectedResult = $false
}
) {
Mock -ModuleName Maester Get-MtExo {
if ($Request -eq 'AcceptedDomain') {
return [PSCustomObject]@{
DomainName = $DomainName
InitialDomain = $InitialDomain
IsCoexistenceDomain = $IsCoexistenceDomain
SendingFromDomainDisabled = $SendingFromDomainDisabled
}
}

return @()
}

$result = & $CommandName
if ($null -eq $ExpectedResult) {
$result | Should -BeNullOrEmpty
} else {
$result | Should -Be $ExpectedResult
}
Should -Invoke Get-MailAuthenticationRecord -ModuleName Maester -Exactly 0
}
}
6 changes: 6 additions & 0 deletions website/contributors/contributors.yml
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Original file line number Diff line number Diff line change
Expand Up @@ -30,6 +30,12 @@ alexandair:
name: Aleksandar Nikolić
title: Microsoft MVP

amlhive-tech:
name: Haris Habib
company: AMLHIVE
emails:
- tech@amlhive.com.au

amandaw33:

andremieth:
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