An exploitable heap based buffer overflow vulnerability exists in the 'read_biff_next_record function' of FreeXL 1.0.3 and earlier. A specially crafted XLS file can cause a memory corruption resulting in remote code execution. An attacker can send malicious XLS file to trigger this vulnerability.
CWE-787 - Out-of-Bounds Write
Out-of-bounds write vulnerability is a memory access bug that allows software to write data past the end or before the beginning of the intended buffer. This may result in the corruption of data, a crash, or arbitrary code execution.