diff --git a/apps/dav/lib/Connector/Sabre/Node.php b/apps/dav/lib/Connector/Sabre/Node.php
index 2b77dc08e8dbe..7fa698670864a 100644
--- a/apps/dav/lib/Connector/Sabre/Node.php
+++ b/apps/dav/lib/Connector/Sabre/Node.php
@@ -421,7 +421,7 @@ public function getNode(): \OCP\Files\Node {
 		return $this->node;
 	}
 
-	protected function sanitizeMtime($mtimeFromRequest) {
+	protected function sanitizeMtime(string $mtimeFromRequest): int {
 		return MtimeSanitizer::sanitizeMtime($mtimeFromRequest);
 	}
 }