Create Block-OutboundConnectionsForAnApp.ps1

Author: bastienperez

Windows/Block-OutboundConnectionsForAnApp.ps1

@@ -0,0 +1,54 @@
+# block outbound connections for an .exe path
+[CmdletBinding()]
+param (
+    [Parameter(Mandatory = $true, HelpMessage = "The path to the application")]
+    [String]$ApplicationPath
+)
+
+
+# Test if application exists
+if (-not (Test-Path $ApplicationPath)) {
+    Write-Warning "'$ApplicationPath' does not exist"
+    return
+}
+
+$fileInfo = Get-Item $ApplicationPath
+$appName = $fileInfo.Name
+$productName = $fileInfo.VersionInfo.ProductName
+$string = ""
+
+if (-not [string]::IsNullOrEmpty($productName)) {
+    $string = $productName.Trim()
+}
+else {
+    $string = $fileInfo.BaseName.Trim()
+}
+
+if (-not [string]::IsNullOrEmpty($appName)) {
+    $string = $string + " - " + $appName
+}
+
+$ruleName = "[Custom] Block outbound access for $string ($applicationPath)"
+
+# Test if the rule already exists
+try {
+    $ruleExists = [boolean](Get-NetFirewallRule -Direction Outbound  | Where-Object { $_.DisplayName -eq "$ruleName" })
+}
+catch {
+    Write-Warning "Failed to check if the rule already exists $($_.Exception.Message)."
+}
+
+if ($ruleExists) {
+    Write-Warning "The rule '$ruleName' already exists"
+    return
+}
+
+# create a new rule
+try {
+    Write-Host -ForegroundColor Cyan "Creating a new rule to block outbound connections for the application: $ApplicationPath"
+    New-NetFirewallRule -DisplayName $ruleName -Direction Outbound -Program $ApplicationPath -Action Block -Enabled True -ErrorAction Stop
+    Write-Host -ForegroundColor Green "The rule has been created successfully."
+}
+catch {
+    Write-Host "Failed to create the rule. The rule may already exist."
+}