diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index 5c388c4044..87b6163cc4 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -1881,6 +1881,10 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
                 int last = 0;
                 for (i = 0; i < 64; i++) {
                     int j;
+                    if (get_bits_left(gb) < 8) {
+                        av_log(s->avctx, AV_LOG_ERROR, "insufficient data for custom matrix\n");
+                        return AVERROR_INVALIDDATA;
+                    }
                     v = get_bits(gb, 8);
                     if (v == 0)
                         break;
@@ -1904,6 +1908,10 @@ static int decode_vol_header(Mpeg4DecContext *ctx, GetBitContext *gb)
                 int last = 0;
                 for (i = 0; i < 64; i++) {
                     int j;
+                    if (get_bits_left(gb) < 8) {
+                        av_log(s->avctx, AV_LOG_ERROR, "insufficient data for custom matrix\n");
+                        return AVERROR_INVALIDDATA;
+                    }
                     v = get_bits(gb, 8);
                     if (v == 0)
                         break;