diff --git a/src/GZCTF/Models/Internal/Configs.cs b/src/GZCTF/Models/Internal/Configs.cs
index 72f38bac2..69516b3c7 100644
--- a/src/GZCTF/Models/Internal/Configs.cs
+++ b/src/GZCTF/Models/Internal/Configs.cs
@@ -226,6 +226,7 @@ public class SmtpConfig
 {
     public string? Host { get; set; } = "127.0.0.1";
     public int? Port { get; set; } = 587;
+    public bool BypassCertVerify { get; set; }
 }
 
 public class EmailConfig
diff --git a/src/GZCTF/Services/Mail/MailSender.cs b/src/GZCTF/Services/Mail/MailSender.cs
index f973f9abd..fcb5b956d 100644
--- a/src/GZCTF/Services/Mail/MailSender.cs
+++ b/src/GZCTF/Services/Mail/MailSender.cs
@@ -47,6 +47,9 @@ public MailSender(
                            !cipherName.EndsWith("NULL");
                 }));
 
+        _smtpClient.ServerCertificateValidationCallback = (_, _, _, errors)
+            => errors is SslPolicyErrors.None || options.Value.Smtp?.BypassCertVerify is true;
+
         Task.Factory.StartNew(MailSenderWorker, _cancellationToken, TaskCreationOptions.LongRunning,
             TaskScheduler.Default);
     }