The Spreadsheet::ParseXLSX package before 0.28 for Perl can encounter an out-of-memory condition during parsing of a crafted XLSX document. This occurs because the memoize implementation does not have appropriate constraints on merged cells.

The Spreadsheet::ParseXLSX package before 0.30 for Perl allows XXE attacks because it neglects to use the no_xxe option of XML::Twig.