Merge pull request #5697 from LibreSign/fix/validate-return-of-poppler

fix: valdiate return of poppler

Author: vitormattos

lib/Handler/SignEngine/Pkcs12Handler.php

@@ -311,6 +311,9 @@ private function parseDistinguishedNameWithMultipleValues(string $dn): array {
 
 		foreach ($pairs as $pair) {
 			[$key, $value] = explode('=', $pair, 2);
+			if (empty($key) || empty($value)) {
+				throw new LibresignException($this->l10n->t('Invalid value: %s.', ['Signer full Distinguished Name: ' . $pair]));
+			}
 			$key = trim($key);
 			$value = trim($value);
 			$value = trim($value, '"');