diff --git a/apps/files_encryption/lib/session.php b/apps/files_encryption/lib/session.php
index 34913039b0ccbcf1748daa6c2499d8c52a8fbbe2..d60c386fb1cb7d84b6418c9c9536cf7c8f293a4f 100644
--- a/apps/files_encryption/lib/session.php
+++ b/apps/files_encryption/lib/session.php
@@ -150,12 +150,11 @@ class Session
 	 */
 	public function getPublicSharePrivateKey() {
 
-		if (isset($_SESSION['publicSharePrivateKey']) && !empty($_SESSION['publicSharePrivateKey'])) {
-			return $_SESSION['publicSharePrivateKey'];
+		if (!is_null( \OC::$session->get('publicSharePrivateKey') )) {
+			return \OC::$session->get('publicSharePrivateKey');
 		} else {
 			return false;
 		}
-
 	}