diff --git a/src/Symfony/Component/Mailer/Bridge/Mailgun/RemoteEvent/MailgunPayloadConverter.php b/src/Symfony/Component/Mailer/Bridge/Mailgun/RemoteEvent/MailgunPayloadConverter.php
index 02e04104ac6b9..68dc6e96ca267 100644
--- a/src/Symfony/Component/Mailer/Bridge/Mailgun/RemoteEvent/MailgunPayloadConverter.php
+++ b/src/Symfony/Component/Mailer/Bridge/Mailgun/RemoteEvent/MailgunPayloadConverter.php
@@ -55,8 +55,8 @@ public function convert(array $payload): AbstractMailerEvent
         }
         $event->setDate($date);
         $event->setRecipientEmail($payload['recipient']);
-        $event->setMetadata($payload['user-variables']);
-        $event->setTags($payload['tags']);
+        $event->setMetadata($payload['user-variables'] ?? []);
+        $event->setTags($payload['tags'] ?? []);
 
         return $event;
     }
@@ -78,10 +78,10 @@ private function getReason(array $payload): string
         if ('' !== ($payload['delivery-status']['description'] ?? '')) {
             return $payload['delivery-status']['description'];
         }
-        if ('' !== $payload['delivery-status']['message']) {
+        if ('' !== ($payload['delivery-status']['message'] ?? '')) {
             return $payload['delivery-status']['message'];
         }
-        if ('' !== $payload['reason']) {
+        if ('' !== ($payload['reason'] ?? '')) {
             return $payload['reason'];
         }
 
diff --git a/src/Symfony/Component/Mailer/Bridge/Mailgun/Tests/Webhook/Fixtures/accepted.json b/src/Symfony/Component/Mailer/Bridge/Mailgun/Tests/Webhook/Fixtures/accepted.json
new file mode 100644
index 0000000000000..d349f3f331f54
--- /dev/null
+++ b/src/Symfony/Component/Mailer/Bridge/Mailgun/Tests/Webhook/Fixtures/accepted.json
@@ -0,0 +1,39 @@
+{
+  "signature":{
+    "token": "885894756b6c371a377f5f9516d60a4db497ad27d4931ed215",
+    "timestamp": "1661621710",
+    "signature": "606307bb55b72686b1b2a2c8c37ae6e6ec89496592bac4a4eee5a346337d04a5"
+  },
+  "event-data":{
+    "event":"accepted",
+    "id":"4o7-z86dSkSI54c6IudeuA",
+    "timestamp":1707402341.91242,
+    "api-key-id":"##REDACTED##",
+    "envelope":{
+      "sender":"postmaster@mg.herehaveth.is",
+      "targets":"ben@##REDACTED##",
+      "transport":"smtp"
+    },
+    "flags":{
+      "is-authenticated":true,
+      "is-test-mode":false
+    },
+    "message":{
+      "headers":{
+        "message-id":"##REDACTED##",
+        "from":"\"Here, have this\" <hello@herehaveth.is>",
+        "to":"alice@example.com",
+        "subject":"Please verify your email address."
+      },
+      "size":2411
+    },
+    "storage":{
+      "key":"##REDACTED##",
+      "url":"https:\/\/storage-us-east4.api.mailgun.net\/v3\/domains\/##REDACTED##"
+    },
+    "method":"HTTP",
+    "log-level":"info",
+    "recipient":"alice@example.com",
+    "recipient-domain":"example.com"
+  }
+}
diff --git a/src/Symfony/Component/Mailer/Bridge/Mailgun/Tests/Webhook/Fixtures/accepted.php b/src/Symfony/Component/Mailer/Bridge/Mailgun/Tests/Webhook/Fixtures/accepted.php
new file mode 100644
index 0000000000000..abe8e3d5af301
--- /dev/null
+++ b/src/Symfony/Component/Mailer/Bridge/Mailgun/Tests/Webhook/Fixtures/accepted.php
@@ -0,0 +1,9 @@
+<?php
+
+use Symfony\Component\RemoteEvent\Event\Mailer\MailerDeliveryEvent;
+
+$wh = new MailerDeliveryEvent(MailerDeliveryEvent::RECEIVED, '4o7-z86dSkSI54c6IudeuA', json_decode(file_get_contents(str_replace('.php', '.json', __FILE__)), true, flags: JSON_THROW_ON_ERROR)['event-data']);
+$wh->setRecipientEmail('alice@example.com');
+$wh->setDate(\DateTimeImmutable::createFromFormat('U.u', '1707402341.91242'));
+
+return $wh;
diff --git a/src/Symfony/Component/Mailer/Bridge/Mailgun/Webhook/MailgunRequestParser.php b/src/Symfony/Component/Mailer/Bridge/Mailgun/Webhook/MailgunRequestParser.php
index b6ed83bc0ccbc..1a38b33bf8114 100644
--- a/src/Symfony/Component/Mailer/Bridge/Mailgun/Webhook/MailgunRequestParser.php
+++ b/src/Symfony/Component/Mailer/Bridge/Mailgun/Webhook/MailgunRequestParser.php
@@ -50,8 +50,6 @@ protected function doParse(Request $request, #[\SensitiveParameter] string $secr
             || !isset($content['signature']['token'])
             || !isset($content['signature']['signature'])
             || !isset($content['event-data']['event'])
-            || !isset($content['event-data']['tags'])
-            || !isset($content['event-data']['user-variables'])
         ) {
             throw new RejectWebhookException(406, 'Payload is malformed.');
         }

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