Given the following code containing errors, provide Common Weakness Enumeration (CWE) identifiers and corresponding messages in JSON format. Each identified weakness should have a unique entry in the JSON array.
    Code: QPDF::read_xrefTable(qpdf_offset_t xref_offset)
{
    std::vector<QPDFObjGen> deleted_items;

    this->m->file->seek(xref_offset, SEEK_SET);
    bool done = false;
    while (! done)
    {
        char linebuf[51];
        memset(linebuf, 0, sizeof(linebuf));
        this->m->file->read(linebuf, sizeof(linebuf) - 1);
	std::string line = linebuf;
        int obj = 0;
        int num = 0;
        int bytes = 0;
        if (! parse_xrefFirst(line, obj, num, bytes))
	{
	    QTC::TC("qpdf", "QPDF invalid xref");
	    throw QPDFExc(qpdf_e_damaged_pdf, this->m->file->getName(),
			  "xref table", this->m->file->getLastOffset(),
			  "xref syntax invalid");
	}
        this->m->file->seek(this->m->file->getLastOffset() + bytes, SEEK_SET);
	for (qpdf_offset_t i = obj; i - num < obj; ++i)
	{
	    if (i == 0)
	    {
		// This is needed by checkLinearization()
		this->m->first_xref_item_offset = this->m->file->tell();
	    }
	    std::string xref_entry = this->m->file->readLine(30);
            // For xref_table, these will always be small enough to be ints
	    qpdf_offset_t f1 = 0;
	    int f2 = 0;
	    char type = '\0';
            if (! parse_xrefEntry(xref_entry, f1, f2, type))
	    {
		QTC::TC("qpdf", "QPDF invalid xref entry");
		throw QPDFExc(
		    qpdf_e_damaged_pdf, this->m->file->getName(),
		    "xref table", this->m->file->getLastOffset(),
		    "invalid xref entry (obj=" +
		    QUtil::int_to_string(i) + ")");
	    }
	    if (type == 'f')
	    {
		// Save deleted items until after we've checked the
		// XRefStm, if any.
		deleted_items.push_back(QPDFObjGen(i, f2));
	    }
	    else
	    {
		insertXrefEntry(i, 1, f1, f2);
	    }
	}
	qpdf_offset_t pos = this->m->file->tell();
	QPDFTokenizer::Token t = readToken(this->m->file);
	if (t == QPDFTokenizer::Token(QPDFTokenizer::tt_word, "trailer"))
	{
	    done = true;
	}
	else
	{
	    this->m->file->seek(pos, SEEK_SET);
	}
    }

    // Set offset to previous xref table if any
    QPDFObjectHandle cur_trailer =
	readObject(this->m->file, "trailer", 0, 0, false);
    if (! cur_trailer.isDictionary())
    {
	QTC::TC("qpdf", "QPDF missing trailer");
	throw QPDFExc(qpdf_e_damaged_pdf, this->m->file->getName(),
		      "", this->m->file->getLastOffset(),
		      "expected trailer dictionary");
    }

    if (! this->m->trailer.isInitialized())
    {
	setTrailer(cur_trailer);

	if (! this->m->trailer.hasKey("/Size"))
	{
	    QTC::TC("qpdf", "QPDF trailer lacks size");
	    throw QPDFExc(qpdf_e_damaged_pdf, this->m->file->getName(),
			  "trailer", this->m->file->getLastOffset(),
			  "trailer dictionary lacks /Size key");
	}
	if (! this->m->trailer.getKey("/Size").isInteger())
	{
	    QTC::TC("qpdf", "QPDF trailer size not integer");
	    throw QPDFExc(qpdf_e_damaged_pdf, this->m->file->getName(),
			  "trailer", this->m->file->getLastOffset(),
			  "/Size key in trailer dictionary is not "
			  "an integer");
	}
    }

    if (cur_trailer.hasKey("/XRefStm"))
    {
	if (this->m->ignore_xref_streams)
	{
	    QTC::TC("qpdf", "QPDF ignoring XRefStm in trailer");
	}
	else
	{
	    if (cur_trailer.getKey("/XRefStm").isInteger())
	    {
		// Read the xref stream but disregard any return value
		// -- we'll use our trailer's /Prev key instead of the
		// xref stream's.
		(void) read_xrefStream(
		    cur_trailer.getKey("/XRefStm").getIntValue());
	    }
	    else
	    {
		throw QPDFExc(qpdf_e_damaged_pdf, this->m->file->getName(),
			      "xref stream", xref_offset,
			      "invalid /XRefStm");
	    }
	}
    }

    // Handle any deleted items now that we've read the /XRefStm.
    for (std::vector<QPDFObjGen>::iterator iter = deleted_items.begin();
	 iter != deleted_items.end(); ++iter)
    {
	QPDFObjGen& og = *iter;
	insertXrefEntry(og.getObj(), 0, 0, og.getGen());
    }

    if (cur_trailer.hasKey("/Prev"))
    {
	if (! cur_trailer.getKey("/Prev").isInteger())
	{
	    QTC::TC("qpdf", "QPDF trailer prev not integer");
	    throw QPDFExc(qpdf_e_damaged_pdf, this->m->file->getName(),
			  "trailer", this->m->file->getLastOffset(),
			  "/Prev key in trailer dictionary is not "
			  "an integer");
	}
	QTC::TC("qpdf", "QPDF prev key in trailer dictionary");
	xref_offset = cur_trailer.getKey("/Prev").getIntValue();
    }
    else
    {
	xref_offset = 0;
    }

    return xref_offset;
} ; Sample JSON Format Confermily Expected output: "examples" => "cwe": "xxx"; "message": "xxx"
    
 'cwe': ['CWE-787'], 'message': 'Fix sign and conversion warnings (major)

This makes all integer type conversions that have potential data loss
explicit with calls that do range checks and raise an exception. After
this commit, qpdf builds with no warnings when -Wsign-conversion
-Wconversion is used with gcc or clang or when -W3 -Wd4800 is used
with MSVC. This significantly reduces the likelihood of potential
crashes from bogus integer values.

There are some parts of the code that take int when they should take
size_t or an offset. Such places would make qpdf not support files
with more than 2^31 of something that usually wouldn't be so large. In
the event that such a file shows up and is valid, at least qpdf would
raise an error in the right spot so the issue could be legitimately
addressed rather than failing in some weird way because of a silent
overflow condition.'