diff --git a/lib/private/Files/Storage/Wrapper/Encryption.php b/lib/private/Files/Storage/Wrapper/Encryption.php
index 03d4038186f..465971d1345 100644
--- a/lib/private/Files/Storage/Wrapper/Encryption.php
+++ b/lib/private/Files/Storage/Wrapper/Encryption.php
@@ -464,6 +464,7 @@ class Encryption extends Wrapper {
 			if (strlen($lastChunkContentEncrypted) > $blockSize) {
 				$newUnencryptedSize += $unencryptedBlockSize;
 				$lastChunkContentEncrypted = substr($lastChunkContentEncrypted, $blockSize);
+				$lastChunkNr++;
 			}
 		}