diff --git a/src/peers.c b/src/peers.c
index 276e5cece..9a0f3cbdf 100644
--- a/src/peers.c
+++ b/src/peers.c
@@ -1609,8 +1609,11 @@ static int peer_treat_updatemsg(struct appctx *appctx, struct peer *p, int updt,
 			dc = p->dcache;
 			if (*msg_cur == end) {
 				/* Dictionary entry key without value. */
-				if (id > dc->max_entries)
-					break;
+				if (id > dc->max_entries) {
+					TRACE_PROTO("malformed message", PEERS_EV_UPDTMSG,
+					            NULL, p, NULL, &id);
+					goto malformed_unlock;
+				}
 				/* IDs sent over the network are numbered from 1. */
 				de = dc->rx[id - 1].de;
 			}