static int h264_handle_packet_fu_a(AVFormatContext *ctx, PayloadContext *data, AVPacket *pkt,
                                   const uint8_t *buf, int len,
                                   int *nal_counters, int nal_mask)
{
    uint8_t fu_indicator, fu_header, start_bit, nal_type, nal;

    if (len < 3) {
        av_log(ctx, AV_LOG_ERROR, "Too short data for FU-A H.264 RTP packet\n");
        return AVERROR_INVALIDDATA;
    }

    fu_indicator = buf[0];
    fu_header    = buf[1];
    start_bit    = fu_header >> 7;
    nal_type     = fu_header & 0x1f;
    nal          = fu_indicator & 0xe0 | nal_type;

    buf += 2;
    len -= 2;

    if (start_bit && nal_counters)
        nal_counters[nal_type & nal_mask]++;
    return ff_h264_handle_frag_packet(pkt, buf, len, start_bit, &nal, 1);
}

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.