xlsxio through 0.2.37 NULL Pointer Dereference via Worksheet Relationship Without Id

xlsxio through 0.2.37 contains a NULL pointer dereference vulnerability in main_sheet_get_sheetfile_expat_callback_element_start() in lib/xlsxio_read.c that allows attackers to crash applications via crafted files. Attackers can supply a .xlsx file whose workbook.xml.rels contains a worksheet Relationship lacking an Id attribute, crashing the process when xlsxioread_sheet_open() is called.

xlsxio v0.1.2 to v0.2.34 was discovered to contain a free of uninitialized pointer in the xlsxioread_sheetlist_close() function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted XLSX file.