diff --git a/app/Http/Middleware/StartFireflySession.php b/app/Http/Middleware/StartFireflySession.php
index eaf9b8ff9e..2f333ef4ac 100644
--- a/app/Http/Middleware/StartFireflySession.php
+++ b/app/Http/Middleware/StartFireflySession.php
@@ -42,16 +42,20 @@ class StartFireflySession extends StartSession
      */
     protected function storeCurrentUrl(Request $request, $session): void
     {
-        $url          = $request->fullUrl();
-        $forbiddenWords = strpos($url, 'offline') || strpos($url, 'jscript') || strpos($url, 'delete') || strpos($url, '/login') || strpos($url, '/json') || strpos($url, 'serviceworker') || strpos($url, '/attachments/view');
+        $url     = $request->fullUrl();
+        $safeUrl = app('steam')->getSafeUrl($url, route('index'));
 
-        if (false === $forbiddenWords
-            && 'GET' === $request->method()
-            && !$request->ajax()) {
-            //Log::debug(sprintf('Redirect is now "%s".', $url));
-            $session->setPreviousUrl($url);
+        if ($url !== $safeUrl) {
+            //Log::debug(sprintf('storeCurrentUrl: converted "%s" to "%s", so will not use it.', $url, $safeUrl));
             return;
         }
-        //Log::debug(sprintf('Refuse to set "%s" as current URL.', $url));
+
+        if ('GET' === $request->method() && !$request->ajax()) {
+            //Log::debug(sprintf('storeCurrentUrl: Redirect is now "%s".', $safeUrl));
+            $session->setPreviousUrl($safeUrl);
+
+            return;
+        }
+        //Log::debug(sprintf('storeCurrentUrl: Refuse to set "%s" as current URL.', $safeUrl));
     }
 }
diff --git a/app/Support/Steam.php b/app/Support/Steam.php
index 5287febaee..cf911f9a15 100644
--- a/app/Support/Steam.php
+++ b/app/Support/Steam.php
@@ -31,7 +31,9 @@ use FireflyIII\Models\TransactionCurrency;
 use FireflyIII\Repositories\Account\AccountRepositoryInterface;
 use Illuminate\Support\Collection;
 use JsonException;
+use Log;
 use stdClass;
+use Str;
 
 /**
  * Class Steam.
@@ -41,6 +43,53 @@ use stdClass;
 class Steam
 {
 
+    /**
+     * Returns the previous URL but refuses to send you to specific URLs.
+     *
+     * - outside domain
+     * - to JS files, API or JSON routes
+     *
+     * Uses the session's previousUrl() function as inspired by GitHub user @z1r0-
+     *
+     *  session()->previousUrl() uses getSafeUrl() so we can safely return it:
+     *
+     * @return string
+     */
+    public function getSafePreviousUrl(): string
+    {
+        //Log::debug(sprintf('getSafePreviousUrl: "%s"', session()->previousUrl()));
+        return session()->previousUrl() ?? route('index');
+    }
+
+    /**
+     * Make sure URL is safe.
+     *
+     * @param string $unknownUrl
+     * @param string $safeUrl
+     *
+     * @return string
+     */
+    public function getSafeUrl(string $unknownUrl, string $safeUrl): string
+    {
+        //Log::debug(sprintf('getSafeUrl(%s, %s)', $unknownUrl, $safeUrl));
+        $returnUrl   = $safeUrl;
+        $unknownHost = parse_url($unknownUrl, PHP_URL_HOST);
+        $safeHost    = parse_url($safeUrl, PHP_URL_HOST);
+
+        if (null !== $unknownHost && $unknownHost === $safeHost) {
+            $returnUrl = $unknownUrl;
+        }
+
+        // URL must not lead to weird pages
+        $forbiddenWords = ['jscript', 'json', 'debug', 'serviceworker', 'offline', 'delete', '/login', '/attachments/view'];
+        if (Str::contains($returnUrl, $forbiddenWords)) {
+            $returnUrl = $safeUrl;
+        }
+
+        return $returnUrl;
+    }
+
+
     /**
      * @param Account $account
      * @param Carbon  $date