diff --git a/libavcodec/cinepak.c b/libavcodec/cinepak.c
index f651c489bf..4a9d0b44c5 100644
--- a/libavcodec/cinepak.c
+++ b/libavcodec/cinepak.c
@@ -443,10 +443,13 @@ static int cinepak_decode_frame(AVCodecContext *avctx,
         return ret;
 
     if (s->palette_video) {
-        const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
-        if (pal) {
+        int size;
+        const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
+        if (pal && size == AVPALETTE_SIZE) {
             s->frame->palette_has_changed = 1;
             memcpy(s->pal, pal, AVPALETTE_SIZE);
+        } else if (pal) {
+            av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
         }
     }