diff --git a/libavformat/nutdec.c b/libavformat/nutdec.c
index 5fd2a40f42..7da6f2c441 100644
--- a/libavformat/nutdec.c
+++ b/libavformat/nutdec.c
@@ -341,7 +341,7 @@ static int decode_main_header(NUTContext *nut)
     }
 
     // flags had been effectively introduced in version 4
-    if (nut->version > NUT_STABLE_VERSION) {
+    if (nut->version > 3 && end > avio_tell(bc) + 4) {
         nut->flags = ffio_read_varlen(bc);
     }