Block truncated cookies (obsolete)

Computer and userIntune-readyBlockTruncatedCookies

Supported on Microsoft Edge version 123-131, Windows 7 or later

155.0.4283.62

What it does

OBSOLETE: This policy is obsolete and doesn't work after Microsoft Edge 131. This policy provides a temporary opt-out for changes to how Microsoft Edge handles cookies set via JavaScript that contain certain control characters (NULL, carriage return, and line feed). Previously, the presence of any of these characters in a cookie string would cause it to be truncated but still set. Now, the presence of these characters will cause the whole cookie string to be ignored. If you enable or don't configure this policy, the new behavior is enabled. If you disable this policy, the old behavior is enabled. This policy is obsolete because this policy was originally implemented as a safety measure if there was a breakage, but none have been reported.

What it writes

Hive: HKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry key: Software\Policies\Microsoft\Edge\WebView2
Value name: BlockTruncatedCookies
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\WebView2]
"BlockTruncatedCookies"=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: Block truncated cookies (obsolete)
# Name: BlockTruncatedCookies
# Scope: Machine
# State: Enabled
# Source: msedgewebview2.admx

Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\WebView2' -Name 'BlockTruncatedCookies' -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_msedgewebview2/BlockTruncatedCookies

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_msedgewebview2/BlockTruncatedCookies</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: Block truncated cookies (obsolete)
# Name: BlockTruncatedCookies
# Scope: Machine
# State: Enabled
# Source: msedgewebview2.admx

$isMatch = Test-RegistryValueEquals -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\WebView2' -Name 'BlockTruncatedCookies' -Kind 'DWord' -Expected 1
if (-not $isMatch) {
    $reasons.Add('Value mismatch: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\WebView2\BlockTruncatedCookies') | 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: Block truncated cookies (obsolete)
# Name: BlockTruncatedCookies
# Scope: Machine
# State: Enabled
# Source: msedgewebview2.admx

Set-RegistryValue -Path 'Registry::HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge\WebView2' -Name 'BlockTruncatedCookies' -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: BlockTruncatedCookies
Namespace: Microsoft.Policies.WebView2
Template file: msedgewebview2.admx
Release: Microsoft Edge 155.0.4283.62 · file set 0a733b0040dbbf02…

Definition, editor controls and support

Definition

<policy class="Both" displayName="$(string.BlockTruncatedCookies)" explainText="$(string.BlockTruncatedCookies_Explain)" key="Software\Policies\Microsoft\Edge\WebView2" name="BlockTruncatedCookies" presentation="$(presentation.BlockTruncatedCookies)" valueName="BlockTruncatedCookies" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
      <parentCategory ref="Microsoft.Policies.WebView2:Network" />
      <supportedOn ref="Microsoft.Policies.WebView2:OBSOLETE_WIN7_V123_V131" />
      <enabledValue>
        <decimal value="1" />
      </enabledValue>
      <disabledValue>
        <decimal value="0" />
      </disabledValue>
    </policy>

Editor controls

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

Supported platforms and category

Microsoft.Policies.WebView2:category:Network
<category displayName="$(string.Network_group)" name="Network" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
      <parentCategory ref="Microsoft.Policies.WebView2:microsoft_edge_webview2" />
    </category>
Microsoft.Policies.WebView2:category:microsoft_edge_webview2
<category displayName="$(string.microsoft_edge_webview2)" name="microsoft_edge_webview2" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.WebView2:definition:OBSOLETE_WIN7_V123_V131
<definition displayName="$(string.OBSOLETE_WIN7_V123_V131)" name="OBSOLETE_WIN7_V123_V131" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
Microsoft.Policies.WebView2:category:Network
<category displayName="$(string.Network_group)" name="Network" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions">
      <parentCategory ref="Microsoft.Policies.WebView2:microsoft_edge_webview2" />
    </category>
<strings><string id="Microsoft.Policies.WebView2:Network_group">Network settings</string></strings>
Microsoft.Policies.WebView2:category:microsoft_edge_webview2
<category displayName="$(string.microsoft_edge_webview2)" name="microsoft_edge_webview2" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.WebView2:microsoft_edge_webview2">Microsoft Edge WebView2</string></strings>
Microsoft.Policies.WebView2:definition:OBSOLETE_WIN7_V123_V131
<definition displayName="$(string.OBSOLETE_WIN7_V123_V131)" name="OBSOLETE_WIN7_V123_V131" xmlns="http://schemas.microsoft.com/GroupPolicy/2006/07/PolicyDefinitions" />
<strings><string id="Microsoft.Policies.WebView2:OBSOLETE_WIN7_V123_V131">Microsoft Edge version 123-131, Windows 7 or later</string></strings>