const char *avcodec_get_name(enum AVCodecID id)
{
    const AVCodecDescriptor *cd;
    AVCodec *codec;

    if (id == AV_CODEC_ID_NONE)
        return "none";
    cd = avcodec_descriptor_get(id);
    if (cd)
        return cd->name;
    av_log(NULL, AV_LOG_WARNING, "Codec 0x%x is not in the full list.\n", id);
    codec = avcodec_find_decoder(id);
    if (codec)
        return codec->name;
    codec = avcodec_find_encoder(id);
    if (codec)
        return codec->name;
    return "unknown_codec";
}

The product writes data past the end, or before the beginning, of the intended buffer.