Prefer specific key exchange algorithms for TLS
Verified with Microsoft Edge 152.0.4191.53 — updated on July 10, 2026
Supported on: Microsoft Edge version 146, Windows 7 or later
Path in the GPO console
Computer Configuration\Administrative Templates\Microsoft Edge\Cryptography compliance policies User Configuration\Administrative Templates\Microsoft Edge\Cryptography compliance policies Description
This policy configures Microsoft Edge to prioritize certain key agreement algorithms (supported groups) in TLS 1.3 based on compliance requirements. If you set this policy to 'cnsa2', Microsoft Edge prefers the algorithms required for the Commercial National Security Algorithm Suite 2.0 (CNSA 2.0). If you leave this policy unset or set it to 'default', the browser uses its standard key exchange order. This policy does not guarantee negotiation of a specific algorithm. It is designed to help server operators distinguish clients with compliance requirements and apply higher-strength, non-default algorithms only when appropriate. This policy applies only to TLS 1.3 and QUIC. The default cryptography used by Microsoft Edge already provides strong security, but enabling this policy may reduce performance when accessing websites. Policy options mapping: * CNSA2.0 (cnsa2) = Prefer key exchange methods satisfying the requirements of CNSA 2.0 * Default (default) = Use Microsoft Edge's default supported groups Use the preceding information when configuring this policy. Example value: cnsa2
Registry
Software\Policies\Microsoft\Edge Software\Policies\Microsoft\Edge Export Builder
BETAConfigure the state, scope and options, then generate .reg, PowerShell, Intune and SCCM outputs — or add the setting to a multi-setting collection.
These exports write the registry — this is not a managed GPO. ⓘ
Applying both scopes creates an ambiguous configuration (computer takes precedence over user). Only do this intentionally.
.reg file
Windows Registry Editor Version 5.00
; Exported from gporais.com
; Policy: Prefer specific key exchange algorithms for TLS
; State: Enabled
; Scope: Computer (HKLM)
; Supported on: Microsoft Edge version 146, Windows 7 or later
[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Edge]
"PreferSlowKexAlgorithms"="cnsa2"More formats (PowerShell, Intune, SCCM)
PowerShell
# Exported from gporais.com
# Policy: Prefer specific key exchange algorithms for TLS
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 146, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'PreferSlowKexAlgorithms' -Value 'cnsa2' -Type StringIntune XML
No direct Policy CSP / OMA-URI mapping for this policy. Use the Intune Remediation tab, or ingest the ADMX in Intune.Intune Remediation
# === Detection script ===
# Exported from gporais.com
# Policy: Prefer specific key exchange algorithms for TLS
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 146, Windows 7 or later
function Test-RegistryValue {
param(
[Parameter(Mandatory = $true)][string]$Path,
[Parameter(Mandatory = $true)][string]$Name,
[object]$Expected,
[ValidateSet('String', 'DWord', 'MultiString')][string]$Kind = 'String',
[switch]$Absent
)
try {
$item = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction Stop
} catch {
return $Absent.IsPresent
}
if ($Absent.IsPresent) { return $false }
$actual = $item.$Name
if ($Kind -eq 'DWord') { return ([int64]$actual) -eq ([int64]$Expected) }
if ($Kind -eq 'MultiString') {
$actualValues = @($actual)
$expectedValues = @($Expected)
if ($actualValues.Count -ne $expectedValues.Count) { return $false }
for ($i = 0; $i -lt $expectedValues.Count; $i++) {
if ([string]$actualValues[$i] -ne [string]$expectedValues[$i]) { return $false }
}
return $true
}
return [string]$actual -eq [string]$Expected
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Edge' -Name 'PreferSlowKexAlgorithms' -Expected 'cnsa2' -Kind String)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Prefer specific key exchange algorithms for TLS
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 146, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'PreferSlowKexAlgorithms' -Value 'cnsa2' -Type StringSCCM scripts
# Exported from gporais.com
# Policy: Prefer specific key exchange algorithms for TLS
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 146, Windows 7 or later
# SCCM Configuration Item guidance:
# Create a Configuration Item of type "Setting: Script".
# Discovery script: use the Detection script below.
# Remediation script: use the Remediation script below.
# Compliance rule: the Discovery script output equals 'Compliant'.
# === Detection script ===
# Exported from gporais.com
# Policy: Prefer specific key exchange algorithms for TLS
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 146, Windows 7 or later
function Test-RegistryValue {
param(
[Parameter(Mandatory = $true)][string]$Path,
[Parameter(Mandatory = $true)][string]$Name,
[object]$Expected,
[ValidateSet('String', 'DWord', 'MultiString')][string]$Kind = 'String',
[switch]$Absent
)
try {
$item = Get-ItemProperty -LiteralPath $Path -Name $Name -ErrorAction Stop
} catch {
return $Absent.IsPresent
}
if ($Absent.IsPresent) { return $false }
$actual = $item.$Name
if ($Kind -eq 'DWord') { return ([int64]$actual) -eq ([int64]$Expected) }
if ($Kind -eq 'MultiString') {
$actualValues = @($actual)
$expectedValues = @($Expected)
if ($actualValues.Count -ne $expectedValues.Count) { return $false }
for ($i = 0; $i -lt $expectedValues.Count; $i++) {
if ([string]$actualValues[$i] -ne [string]$expectedValues[$i]) { return $false }
}
return $true
}
return [string]$actual -eq [string]$Expected
}
$checks = @(
(Test-RegistryValue -Path 'HKLM:\Software\Policies\Microsoft\Edge' -Name 'PreferSlowKexAlgorithms' -Expected 'cnsa2' -Kind String)
)
if ($checks -notcontains $false) {
Write-Output 'Compliant'
exit 0
}
Write-Output 'Non-compliant'
exit 1
# === Remediation script ===
# Exported from gporais.com
# Policy: Prefer specific key exchange algorithms for TLS
# State: Enabled
# Scope: Computer (HKLM)
# Supported on: Microsoft Edge version 146, Windows 7 or later
$path = 'HKLM:\Software\Policies\Microsoft\Edge'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'PreferSlowKexAlgorithms' -Value 'cnsa2' -Type StringBuilding a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.