diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index 1bb2e4d1a..7de9ae4b5 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -627,7 +627,16 @@ dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok)
 		frag->msg_header.frag_off = 0;
 		}
 	else
+		{
 		frag = (hm_fragment*) item->data;
+		if (frag->msg_header.msg_len != msg_hdr->msg_len)
+			{
+			item = NULL;
+			frag = NULL;
+			goto err;
+			}
+		}
+
 
 	/* If message is already reassembled, this must be a
 	 * retransmit and can be dropped.