Check RSA key usage for server certificates issued by local trust anchors (obsolete)

Computer and userIntune-readyRSAKeyUsageForLocalAnchorsEnabled

Supported on Microsoft Edge version 123-135, Windows 7 or later

155.0.4283.62

What it does

OBSOLETE: This policy is obsolete and doesn't work after Microsoft Edge 135. The X.509 key usage extension declares how the key in a certificate can be used. These instructions ensure certificates aren't used in an unintended context, which protects against a class of cross-protocol attacks on HTTPS and other protocols. HTTPS clients must verify that server certificates match the connection's TLS parameters. Starting in Microsoft Edge 124, this check is always enabled. Microsoft Edge 123 and earlier have the following behavior: If this policy is set to enabled, Microsoft Edge performs this key check. This helps prevent attacks where an attacker manipulates the browser into interpreting a key in ways that the certificate owner didn't intend. If this policy is set to disabled, Microsoft Edge skips this key check-in HTTPS connections that negotiate TLS 1.2 and use an RSA certificate that chains to a local trust anchor. Examples of local trust anchors include policy-provided or user-installed root certificates. In all other cases, the check is performed independent of this policy's setting. If this policy isn't configured, Microsoft Edge behaves as if the policy is enabled. This policy is available for administrators to preview the behavior of a future release, which will enable this check by default. At that point, this policy will remain temporarily available for administrators that need more time to update their certificates to meet the new RSA key usage requirements. Connections that fail this check will fail with the error ERR_SSL_KEY_USAGE_INCOMPATIBLE. Sites that fail with this error likely have a misconfigured certificate. Modern ECDHE_RSA cipher suites use the "digitalSignature" key usage option, while legacy RSA decryption cipher suites use the "keyEncipherment" key usage option. If uncertain, administrators should include both in RSA certificates meant for HTTPS. The policy has been obsoleted starting from Microsoft Edge version 136, but the key check has been always enabled since Microsoft Edge version 124.

What it writes

Hive: HKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry key: Software\Policies\Microsoft\Edge
Value name: RSAKeyUsageForLocalAnchorsEnabled
When enabled: DWORD 1
When disabled: DWORD 0

Configure and deploy

Choose a state; the output below is generated from the template for exactly that.

Enabled · Computer · template defaults

Registry file (.reg)

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge]
"RSAKeyUsageForLocalAnchorsEnabled"=dword:00000001

PowerShell

$ErrorActionPreference = 'Stop'

function Set-RegistryValue {
    param(
        [Parameter(Mandatory = $true)][string] $Path,
        [Parameter(Mandatory = $true)][string] $Name,
        [Parameter(Mandatory = $true)][string] $PropertyType,
        [Parameter(Mandatory = $true)][object] $Value
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        New-Item -Path $Path -Force | Out-Null
    }

    New-ItemProperty -LiteralPath $Path -Name $Name -PropertyType $PropertyType -Value $Value -Force | Out-Null
}

function Remove-RegistryValue {
    param(
        [Parameter(Mandatory = $true)][string] $Path,
        [Parameter(Mandatory = $true)][string] $Name
    )

    if (Test-Path -LiteralPath $Path) {
        Remove-ItemProperty -LiteralPath $Path -Name $Name -Force -ErrorAction SilentlyContinue
    }
}

function Clear-RegistryKeyValues {
    param(
        [Parameter(Mandatory = $true)][string] $Path
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        return
    }

    foreach ($propertyName in (Get-Item -LiteralPath $Path).Property) {
        Remove-ItemProperty -LiteralPath $Path -Name $propertyName -Force -ErrorAction SilentlyContinue
    }
}

# Policy: Check RSA key usage for server certificates issued by local trust anchors (obsolete)
# Name: RSAKeyUsageForLocalAnchorsEnabled
# Scope: Machine
# State: Enabled
# Source: msedge.admx

Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge' -Name 'RSAKeyUsageForLocalAnchorsEnabled' -PropertyType 'DWord' -Value 1

The OMA-URI is an inferred ADMX-backed Policy CSP candidate derived from the source ADMX file name and policy name.
Some Microsoft policies use built-in Policy CSP pages whose area names don't match the ADMX file name, so verify the candidate against Microsoft Learn before deployment.

ADMX profile candidate (OMA-URI)

./Device/Vendor/MSFT/Policy/Config/ADMX_msedge/RSAKeyUsageForLocalAnchorsEnabled

ADMX SyncML candidate

<SyncML xmlns="SYNCML:SYNCML1.2">
  <SyncBody>
    <Replace>
      <CmdID>1</CmdID>
      <Item>
        <Meta>
          <Format>chr</Format>
          <Type>text/plain</Type>
        </Meta>
        <Target>
          <LocURI>./Device/Vendor/MSFT/Policy/Config/ADMX_msedge/RSAKeyUsageForLocalAnchorsEnabled</LocURI>
        </Target>
        <Data>&lt;enabled/&gt;</Data>
      </Item>
    </Replace>
    <Final/>
  </SyncBody>
</SyncML>

Intune remediation scripts

Detection

$ErrorActionPreference = 'Stop'
$reasons = [System.Collections.Generic.List[string]]::new()

function Test-RegistryValueExists {
    param(
        [Parameter(Mandatory = $true)][string] $Path,
        [Parameter(Mandatory = $true)][string] $Name
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        return $false
    }

    return $null -ne (Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction SilentlyContinue)
}

function Test-RegistryValueEquals {
    param(
        [Parameter(Mandatory = $true)][string] $Path,
        [Parameter(Mandatory = $true)][string] $Name,
        [Parameter(Mandatory = $true)][string] $Kind,
        [Parameter(Mandatory = $true)][object] $Expected
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        return $false
    }

    $valueObject = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction SilentlyContinue
    if ($null -eq $valueObject) {
        return $false
    }

    $actual = $valueObject.$Name
    switch ($Kind) {
        'String' { return [string]$actual -ceq [string]$Expected }
        'ExpandString' { return [string]$actual -ceq [string]$Expected }
        'DWord' { return [uint32]$actual -eq [uint32]$Expected }
        'QWord' { return [uint64]$actual -eq [uint64]$Expected }
        'MultiString' {
            $actualArray = @($actual)
            $expectedArray = @($Expected)
            if ($actualArray.Count -ne $expectedArray.Count) { return $false }
            for ($index = 0; $index -lt $actualArray.Count; $index++) {
                if ([string]$actualArray[$index] -cne [string]$expectedArray[$index]) { return $false }
            }
            return $true
        }
        'Binary' {
            $actualArray = [byte[]]$actual
            $expectedArray = [byte[]]$Expected
            if ($actualArray.Length -ne $expectedArray.Length) { return $false }
            for ($index = 0; $index -lt $actualArray.Length; $index++) {
                if ($actualArray[$index] -ne $expectedArray[$index]) { return $false }
            }
            return $true
        }
        default { return [string]$actual -ceq [string]$Expected }
    }
}

# Policy: Check RSA key usage for server certificates issued by local trust anchors (obsolete)
# Name: RSAKeyUsageForLocalAnchorsEnabled
# Scope: Machine
# State: Enabled
# Source: msedge.admx

$isMatch = Test-RegistryValueEquals -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge' -Name 'RSAKeyUsageForLocalAnchorsEnabled' -Kind 'DWord' -Expected 1
if (-not $isMatch) {
    $reasons.Add('Value mismatch: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\RSAKeyUsageForLocalAnchorsEnabled') | Out-Null
}

if ($reasons.Count -eq 0) {
    Write-Output 'Compliant'
    exit 0
}

$reasons | ForEach-Object { Write-Output $_ }
exit 1

Remediation

$ErrorActionPreference = 'Stop'

function Set-RegistryValue {
    param(
        [Parameter(Mandatory = $true)][string] $Path,
        [Parameter(Mandatory = $true)][string] $Name,
        [Parameter(Mandatory = $true)][string] $PropertyType,
        [Parameter(Mandatory = $true)][object] $Value
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        New-Item -Path $Path -Force | Out-Null
    }

    New-ItemProperty -LiteralPath $Path -Name $Name -PropertyType $PropertyType -Value $Value -Force | Out-Null
}

function Remove-RegistryValue {
    param(
        [Parameter(Mandatory = $true)][string] $Path,
        [Parameter(Mandatory = $true)][string] $Name
    )

    if (Test-Path -LiteralPath $Path) {
        Remove-ItemProperty -LiteralPath $Path -Name $Name -Force -ErrorAction SilentlyContinue
    }
}

function Clear-RegistryKeyValues {
    param(
        [Parameter(Mandatory = $true)][string] $Path
    )

    if (-not (Test-Path -LiteralPath $Path)) {
        return
    }

    foreach ($propertyName in (Get-Item -LiteralPath $Path).Property) {
        Remove-ItemProperty -LiteralPath $Path -Name $propertyName -Force -ErrorAction SilentlyContinue
    }
}

# Policy: Check RSA key usage for server certificates issued by local trust anchors (obsolete)
# Name: RSAKeyUsageForLocalAnchorsEnabled
# Scope: Machine
# State: Enabled
# Source: msedge.admx

Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge' -Name 'RSAKeyUsageForLocalAnchorsEnabled' -PropertyType 'DWord' -Value 1

History 37 retained releases

150.0.4078.8016 Jul 2026
- Already present in the first release ChangeIntel keeps.

36 later releases left it unchanged.

Template

Internal name: RSAKeyUsageForLocalAnchorsEnabled
Namespace: Microsoft.Policies.Edge
Template file: msedge.admx
Release: Microsoft Edge 155.0.4283.62 · file set 0a733b0040dbbf02…

Definition, editor controls and support

Definition

<policy class="Both" displayName="$(string.RSAKeyUsageForLocalAnchorsEnabled)" explainText="$(string.RSAKeyUsageForLocalAnchorsEnabled_Explain)" key="Software\Policies\Microsoft\Edge" name="RSAKeyUsageForLocalAnchorsEnabled" presentation="$(presentation.RSAKeyUsageForLocalAnchorsEnabled)" valueName="RSAKeyUsageForLocalAnchorsEnabled" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
      <parentCategory ref="Microsoft.Policies.Edge:microsoft_edge" />
      <supportedOn ref="Microsoft.Policies.Edge:OBSOLETE_WIN7_V123_V135" />
      <enabledValue>
        <decimal value="1" />
      </enabledValue>
      <disabledValue>
        <decimal value="0" />
      </disabledValue>
    </policy>

Editor controls

<presentation id="RSAKeyUsageForLocalAnchorsEnabled" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />

Supported platforms and category

Microsoft.Policies.Edge:category:microsoft_edge
<category displayName="$(string.microsoft_edge)" name="microsoft_edge" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.Edge:definition:OBSOLETE_WIN7_V123_V135
<definition displayName="$(string.OBSOLETE_WIN7_V123_V135)" name="OBSOLETE_WIN7_V123_V135" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.Edge:category:microsoft_edge
<category displayName="$(string.microsoft_edge)" name="microsoft_edge" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.Edge:microsoft_edge">Microsoft Edge</string></strings>
Microsoft.Policies.Edge:definition:OBSOLETE_WIN7_V123_V135
<definition displayName="$(string.OBSOLETE_WIN7_V123_V135)" name="OBSOLETE_WIN7_V123_V135" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.Edge:OBSOLETE_WIN7_V123_V135">Microsoft Edge version 123-135, Windows 7 or later</string></strings>