fix(webhooks): add validation to block unsafe webhook URLs

Prevent server-side request forgery (SSRF) attacks by validating webhook URLs before sending requests. Blocks loopback addresses, cloud metadata endpoints, and localhost URLs.

- Add SafeWebhookUrl rule validation in SendWebhookJob.handle()
- Log warning when unsafe URLs are rejected
- Add comprehensive unit tests covering valid and invalid URL scenarios

app/Jobs/SendWebhookJob.php

@@ -9,6 +9,8 @@ use Illuminate\Foundation\Bus\Dispatchable;
 use Illuminate\Queue\InteractsWithQueue;
 use Illuminate\Queue\SerializesModels;
 use Illuminate\Support\Facades\Http;
+use Illuminate\Support\Facades\Log;
+use Illuminate\Support\Facades\Validator;
 
 class SendWebhookJob implements ShouldBeEncrypted, ShouldQueue
 {
@@ -40,6 +42,20 @@ class SendWebhookJob implements ShouldBeEncrypted, ShouldQueue
      */
     public function handle(): void
     {
+        $validator = Validator::make(
+            ['webhook_url' => $this->webhookUrl],
+            ['webhook_url' => ['required', 'url', new \App\Rules\SafeWebhookUrl]]
+        );
+
+        if ($validator->fails()) {
+            Log::warning('SendWebhookJob: blocked unsafe webhook URL', [
+                'url' => $this->webhookUrl,
+                'errors' => $validator->errors()->all(),
+            ]);
+
+            return;
+        }
+
         if (isDev()) {
             ray('Sending webhook notification', [
                 'url' => $this->webhookUrl,

tests/Unit/SendWebhookJobTest.php

@@ -0,0 +1,77 @@
+<?php
+
+use App\Jobs\SendWebhookJob;
+use Illuminate\Support\Facades\Http;
+use Illuminate\Support\Facades\Log;
+use Tests\TestCase;
+
+uses(TestCase::class);
+
+it('sends webhook to valid URLs', function () {
+    Http::fake(['*' => Http::response('ok', 200)]);
+
+    $job = new SendWebhookJob(
+        payload: ['event' => 'test'],
+        webhookUrl: 'https://example.com/webhook'
+    );
+
+    $job->handle();
+
+    Http::assertSent(function ($request) {
+        return $request->url() === 'https://example.com/webhook';
+    });
+});
+
+it('blocks webhook to loopback address', function () {
+    Http::fake();
+    Log::shouldReceive('warning')
+        ->once()
+        ->withArgs(function ($message) {
+            return str_contains($message, 'blocked unsafe webhook URL');
+        });
+
+    $job = new SendWebhookJob(
+        payload: ['event' => 'test'],
+        webhookUrl: 'http://127.0.0.1/admin'
+    );
+
+    $job->handle();
+
+    Http::assertNothingSent();
+});
+
+it('blocks webhook to cloud metadata endpoint', function () {
+    Http::fake();
+    Log::shouldReceive('warning')
+        ->once()
+        ->withArgs(function ($message) {
+            return str_contains($message, 'blocked unsafe webhook URL');
+        });
+
+    $job = new SendWebhookJob(
+        payload: ['event' => 'test'],
+        webhookUrl: 'http://169.254.169.254/latest/meta-data/'
+    );
+
+    $job->handle();
+
+    Http::assertNothingSent();
+});
+
+it('blocks webhook to localhost', function () {
+    Http::fake();
+    Log::shouldReceive('warning')
+        ->once()
+        ->withArgs(function ($message) {
+            return str_contains($message, 'blocked unsafe webhook URL');
+        });
+
+    $job = new SendWebhookJob(
+        payload: ['event' => 'test'],
+        webhookUrl: 'http://localhost/internal-api'
+    );
+
+    $job->handle();
+
+    Http::assertNothingSent();
+});