diff --git a/libavformat/rdt.c b/libavformat/rdt.c
index b9b02a371f..138f110906 100644
--- a/libavformat/rdt.c
+++ b/libavformat/rdt.c
@@ -204,6 +204,8 @@ ff_rdt_parse_header(const uint8_t *buf, int len,
             return -1; /* not followed by a data packet */
 
         pkt_len = AV_RB16(buf+3);
+        if (pkt_len > len)
+            return AVERROR_INVALIDDATA;
         buf += pkt_len;
         len -= pkt_len;
         consumed += pkt_len;