jbig2_parse_extension_segment(Jbig2Ctx *ctx, Jbig2Segment *segment, const uint8_t *segment_data)
{
    uint32_t type = jbig2_get_uint32(segment_data);
    bool reserved = type & 0x20000000;

    /* bool dependent = type & 0x40000000; (NYI) */
    bool necessary = type & 0x80000000;

    if (necessary && !reserved) {
        jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number, "extension segment is marked 'necessary' but " "not 'reservered' contrary to spec");
    }

    switch (type) {
    case 0x20000000:
        return jbig2_comment_ascii(ctx, segment, segment_data);
    case 0x20000002:
        return jbig2_comment_unicode(ctx, segment, segment_data);
    default:
        if (necessary) {
            return jbig2_error(ctx, JBIG2_SEVERITY_FATAL, segment->number, "unhandled necessary extension segment type 0x%08x", type);
        } else {
            return jbig2_error(ctx, JBIG2_SEVERITY_WARNING, segment->number, "unhandled extension segment");
        }
    }
}

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.