Fix security issues: prevent command injection and improve certificate parsing

Co-authored-by: JusterZhu <11714536+JusterZhu@users.noreply.github.com>

Author: Copilot

src/c#/GeneralUpdate.Drivelution/Linux/Implementation/LinuxGeneralDrivelution.cs

@@ -524,7 +524,9 @@ private async Task ParseDebPackageAsync(string debPath, DriverInfo driverInfo, C
         try
         {
             // Try to get package info using dpkg-deb command
-            var output = await ExecuteCommandAsync("dpkg-deb", $"-I {debPath}", cancellationToken);
+            // Use proper argument passing to avoid injection issues
+            var escapedPath = debPath.Replace("'", "'\\''");
+            var output = await ExecuteCommandAsync("dpkg-deb", $"-I '{escapedPath}'", cancellationToken);
             var lines = output.Split('\n');
 
             foreach (var line in lines)
@@ -562,7 +564,9 @@ private async Task ParseRpmPackageAsync(string rpmPath, DriverInfo driverInfo, C
         try
         {
             // Try to get package info using rpm command
-            var output = await ExecuteCommandAsync("rpm", $"-qip {rpmPath}", cancellationToken);
+            // Use proper argument passing to avoid injection issues
+            var escapedPath = rpmPath.Replace("'", "'\\''");
+            var output = await ExecuteCommandAsync("rpm", $"-qip '{escapedPath}'", cancellationToken);
             var lines = output.Split('\n');
 
             foreach (var line in lines)

src/c#/GeneralUpdate.Drivelution/Windows/Implementation/WindowsGeneralDrivelution.cs

@@ -547,23 +547,30 @@ public async Task<List<DriverInfo>> GetDriversFromDirectoryAsync(
                 if (WindowsSignatureHelper.IsFileSigned(filePath))
                 {
                     // Try to extract publisher from certificate
-                    using var cert = System.Security.Cryptography.X509Certificates.X509Certificate.CreateFromSignedFile(filePath);
-                    if (cert != null)
+                    using var cert2 = new System.Security.Cryptography.X509Certificates.X509Certificate2(filePath);
+                    var subject = cert2.Subject;
+                    
+                    // Extract CN (Common Name) from subject
+                    var cnIndex = subject.IndexOf("CN=");
+                    if (cnIndex >= 0)
                     {
-                        using var cert2 = new System.Security.Cryptography.X509Certificates.X509Certificate2(cert);
-                        var subject = cert2.Subject;
+                        var cnStart = cnIndex + 3;
+                        var cnEnd = subject.IndexOf(',', cnStart);
 
-                        // Extract CN (Common Name) from subject
-                        if (subject.Contains("CN="))
+                        string publisher;
+                        if (cnEnd > cnStart)
                         {
-                            var cnStart = subject.IndexOf("CN=") + 3;
-                            var cnEnd = subject.IndexOf(',', cnStart);
-                            var publisher = cnEnd > cnStart ? subject.Substring(cnStart, cnEnd - cnStart) : subject.Substring(cnStart);
-                            
-                            if (!string.IsNullOrEmpty(publisher))
-                            {
-                                driverInfo.TrustedPublishers.Add(publisher);
-                            }
+                            publisher = subject.Substring(cnStart, cnEnd - cnStart);
+                        }
+                        else
+                        {
+                            // No comma after CN, take the rest of the string
+                            publisher = subject.Substring(cnStart);
+                        }
+                        
+                        if (!string.IsNullOrEmpty(publisher))
+                        {
+                            driverInfo.TrustedPublishers.Add(publisher);
                         }
                     }
                 }