diff --git a/src/h3.c b/src/h3.c
index 24162a2ab..831dc19de 100644
--- a/src/h3.c
+++ b/src/h3.c
@@ -612,17 +612,20 @@ static int h3_decode_qcs(struct qcs *qcs, int fin, void *ctx)
 
 			h3s->demux_frame_type = ftype;
 			h3s->demux_frame_len = flen;
+
+			if (!h3_is_frame_valid(h3c, qcs, ftype)) {
+				qcc_emit_cc_app(qcs->qcc, H3_FRAME_UNEXPECTED);
+				return 1;
+			}
+
 			qcs_consume(qcs, hlen);
+			if (!ncb_data(rxbuf, 0))
+				break;
 		}
 
 		flen = h3s->demux_frame_len;
 		ftype = h3s->demux_frame_type;
 
-		if (!h3_is_frame_valid(h3c, qcs, ftype)) {
-			qcc_emit_cc_app(qcs->qcc, H3_FRAME_UNEXPECTED);
-			return 1;
-		}
-
 		/* Do not demux incomplete frames except H3 DATA which can be
 		 * fragmented in multiple HTX blocks.
 		 */