diff --git a/apps/dav/lib/Files/BrowserErrorPagePlugin.php b/apps/dav/lib/Files/BrowserErrorPagePlugin.php
index e1e64b3e6f4..3502acde974 100644
--- a/apps/dav/lib/Files/BrowserErrorPagePlugin.php
+++ b/apps/dav/lib/Files/BrowserErrorPagePlugin.php
@@ -25,6 +25,7 @@ namespace OCA\DAV\Files;
 
 use OC\AppFramework\Http\Request;
 use OC_Template;
+use OCP\AppFramework\Http\ContentSecurityPolicy;
 use OCP\IRequest;
 use Sabre\DAV\Exception;
 use Sabre\DAV\Server;
@@ -82,6 +83,8 @@ class BrowserErrorPagePlugin extends ServerPlugin {
 		$this->server->httpResponse->setStatus($httpCode);
 		$body = $this->generateBody();
 		$this->server->httpResponse->setBody($body);
+		$csp = new ContentSecurityPolicy();
+		$this->server->httpResponse->addHeader('Content-Security-Policy', $csp->buildPolicy());
 		$this->sendResponse();
 	}
 
diff --git a/apps/dav/templates/exception.php b/apps/dav/templates/exception.php
index 9c09cbca444..8f922e22a38 100644
--- a/apps/dav/templates/exception.php
+++ b/apps/dav/templates/exception.php
@@ -22,12 +22,12 @@ style('core', ['styles', 'header']);
 
 /** @param $_ array */
 ?>
-<span class="error error-wide">
+<div class="body-login-container update">
 	<h2><?php p($_['title']) ?></h2>
 
 	<h3><strong><?php p($l->t('Technical details')) ?></strong></h3>
-	<ul>
+	<ul class="infogroup">
 		<li><?php p($l->t('Remote Address: %s', $_['remoteAddr'])) ?></li>
 		<li><?php p($l->t('Request ID: %s', $_['requestID'])) ?></li>
 	</ul>
-</span>
+</div>