static int mov_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    MOVContext *mov = s->priv_data;
    MOVStreamContext *sc;
    AVIndexEntry *sample;
    AVStream *st = NULL;
    int ret;
    mov->fc = s;
 retry:
    sample = mov_find_next_sample(s, &st);
    if (!sample) {
        mov->found_mdat = 0;
        if (!mov->next_root_atom)
            return AVERROR_EOF;
        avio_seek(s->pb, mov->next_root_atom, SEEK_SET);
        mov->next_root_atom = 0;
        if (mov_read_default(mov, s->pb, (MOVAtom){ AV_RL32("root"), INT64_MAX }) < 0 ||
            url_feof(s->pb))
            return AVERROR_EOF;
        av_dlog(s, "read fragments, offset 0x%"PRIx64"\n", avio_tell(s->pb));
        goto retry;
    }
    sc = st->priv_data;
    /* must be done just before reading, to avoid infinite loop on sample */
    sc->current_sample++;

    if (st->discard != AVDISCARD_ALL) {
        if (avio_seek(sc->pb, sample->pos, SEEK_SET) != sample->pos) {
            av_log(mov->fc, AV_LOG_ERROR, "stream %d, offset 0x%"PRIx64": partial file\n",
                   sc->ffindex, sample->pos);
            return AVERROR_INVALIDDATA;
        }
        ret = av_get_packet(sc->pb, pkt, sample->size);
        if (ret < 0)
            return ret;
        if (sc->has_palette) {
            uint8_t *pal;

            pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);
            if (!pal) {
                av_log(mov->fc, AV_LOG_ERROR, "Cannot append palette to packet\n");
            } else {
                memcpy(pal, sc->palette, AVPALETTE_SIZE);
                sc->has_palette = 0;
            }
        }
#if CONFIG_DV_DEMUXER
        if (mov->dv_demux && sc->dv_audio_container) {
            avpriv_dv_produce_packet(mov->dv_demux, pkt, pkt->data, pkt->size, pkt->pos);
            av_free(pkt->data);
            pkt->size = 0;
            ret = avpriv_dv_get_packet(mov->dv_demux, pkt);
            if (ret < 0)
                return ret;
        }
#endif
    }

    pkt->stream_index = sc->ffindex;
    pkt->dts = sample->timestamp;
    if (sc->ctts_data && sc->ctts_index < sc->ctts_count) {
        pkt->pts = pkt->dts + sc->dts_shift + sc->ctts_data[sc->ctts_index].duration;
        /* update ctts context */
        sc->ctts_sample++;
        if (sc->ctts_index < sc->ctts_count &&
            sc->ctts_data[sc->ctts_index].count == sc->ctts_sample) {
            sc->ctts_index++;
            sc->ctts_sample = 0;
        }
        if (sc->wrong_dts)
            pkt->dts = AV_NOPTS_VALUE;
    } else {
        int64_t next_dts = (sc->current_sample < st->nb_index_entries) ?
            st->index_entries[sc->current_sample].timestamp : st->duration;
        pkt->duration = next_dts - pkt->dts;
        pkt->pts = pkt->dts;
    }
    if (st->discard == AVDISCARD_ALL)
        goto retry;
    pkt->flags |= sample->flags & AVINDEX_KEYFRAME ? AV_PKT_FLAG_KEY : 0;
    pkt->pos = sample->pos;
    av_dlog(s, "stream %d, pts %"PRId64", dts %"PRId64", pos 0x%"PRIx64", duration %d\n",
            pkt->stream_index, pkt->pts, pkt->dts, pkt->pos, pkt->duration);
    return 0;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.