Add URL scheme validation to prevent command injection via Process.Start

- HelpMenu.cs: Add https/http scheme validation to OpenUrl() to prevent
  custom URI scheme exploitation
- UpdateWindow.cs: Add scheme validation alongside existing IsFile/IsUnc/IsLoopback
  checks to only allow http/https URLs
- ProgramRoot.cs: Add https:// prefix validation for network-fetched downloadUrl
  before passing to Process.Start with UseShellExecute=true

Co-authored-by: Kvarkas <3611964+Kvarkas@users.noreply.github.com>

.github/workflows/filter-links.yml

@@ -20,7 +20,7 @@ jobs:
         with:
           script: |
             const githubRepoRegex =
-              /\[[^\]]*\]\(https?:\/\/github\.com\/[A-Za-z0-9_.-]+\/[A-Za-z0-9_.-]+[^\s)]*\)|https?:\/\/github\.com\/[A-Za-z0-9_.-]+\/[A-Za-z0-9_.-]+[^\s)]*/gi;
+              /\[[^\]]*\]\((?!https?:\/\/github\.com\/user-attachments\/assets\/)[^\)]*https?:\/\/github\.com\/(?!user-attachments\/assets\/)[A-Za-z0-9_.-]+\/[A-Za-z0-9_.-]+[^\s)]*\)|https?:\/\/github\.com\/(?!user-attachments\/assets\/)[A-Za-z0-9_.-]+\/[A-Za-z0-9_.-]+[^\s)]*/gi;
             
             // CASE 1: Comment
             if (context.payload.comment) {

Directory.Packages.props

@@ -5,8 +5,8 @@
     <NoWarn>$(NoWarn);NU1507;NU1701</NoWarn>
   </PropertyGroup>
   <ItemGroup>
-    <PackageVersion Include="AWSSDK.Core" Version="4.0.3.14" />
-    <PackageVersion Include="AWSSDK.EC2" Version="4.0.76" />
+    <PackageVersion Include="AWSSDK.Core" Version="4.0.3.15" />
+    <PackageVersion Include="AWSSDK.EC2" Version="4.0.76.1" />
     <PackageVersion Include="BouncyCastle.Cryptography" Version="2.6.2" />
     <PackageVersion Include="Castle.Core" Version="5.2.1" />
     <PackageVersion Include="ConsoleControl" Version="1.3.0" />
@@ -25,7 +25,7 @@
     <PackageVersion Include="Microsoft.Data.SqlClient.SNI.runtime" Version="6.0.2" />
     <PackageVersion Include="Microsoft.Extensions.DependencyModel" Version="10.0.3" />
     <PackageVersion Include="Microsoft.Extensions.Configuration.UserSecrets" Version="10.0.3" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.0.1" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
     <PackageVersion Include="Microsoft.NETCore.Platforms" Version="7.0.4" />
     <PackageVersion Include="Microsoft.NETCore.Targets" Version="5.0.0" />
     <PackageVersion Include="Microsoft.VisualStudio.TextTemplating.VSHost" Version="17.14.40265" />

mRemoteNG/App/ProgramRoot.cs

@@ -64,7 +64,9 @@ namespace mRemoteNG.App
                     {
                         try
                         {
-                            Process.Start(new ProcessStartInfo(fileName: downloadUrl) { UseShellExecute = true });
+                            if (!string.IsNullOrEmpty(downloadUrl) &&
+                                downloadUrl.StartsWith("https://", StringComparison.OrdinalIgnoreCase))
+                                Process.Start(new ProcessStartInfo(fileName: downloadUrl) { UseShellExecute = true });
                         }
                         catch (Exception ex)
                         {

mRemoteNG/UI/Menu/msMain/HelpMenu.cs

@@ -204,6 +204,11 @@ namespace mRemoteNG.UI.Menu
         
         private static void OpenUrl(string url)
         {
+            if (string.IsNullOrWhiteSpace(url) ||
+                (!url.StartsWith("https://", StringComparison.OrdinalIgnoreCase) &&
+                 !url.StartsWith("http://", StringComparison.OrdinalIgnoreCase)))
+                return;
+
             var startInfo = new ProcessStartInfo
             {
                 FileName = url,

mRemoteNG/UI/Window/UpdateWindow.cs

@@ -99,6 +99,13 @@ namespace mRemoteNG.UI.Window
                 return;
             }
 
+            // Only allow http/https URLs to prevent exploitation via custom URI schemes
+            if (!linkUri.Scheme.Equals("https", StringComparison.OrdinalIgnoreCase) &&
+                !linkUri.Scheme.Equals("http", StringComparison.OrdinalIgnoreCase))
+            {
+                return;
+            }
+
             var startInfo = new ProcessStartInfo
             {
                 FileName = linkUri.ToString(),

mRemoteNG/mRemoteNG.csproj

@@ -553,10 +553,10 @@
     </EmbeddedResource>
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Update="chromiumembeddedframework.runtime.win-x64" Version="144.0.12" />
+    <PackageReference Update="chromiumembeddedframework.runtime.win-x64" Version="145.0.26" />
   </ItemGroup>
   <ItemGroup Condition="'$(Platform)'=='arm64'">
-    <PackageReference Update="chromiumembeddedframework.runtime.win-arm64" Version="144.0.12" />
+    <PackageReference Update="chromiumembeddedframework.runtime.win-arm64" Version="145.0.26" />
   </ItemGroup>
   <ItemGroup>
     <Service Include="{508349b6-6b84-4df5-91f0-309beebad82d}" />