php: odbc_bindcols function mishandles driver behavior for SQL_WVARCHAR columns

The odbcbindcols function in ext/odbc/phpodbc.c in PHP before 5.6.12 mishandles driver behavior for SQLWVARCHAR columns, which allows remote attackers to cause a denial of service application crash in opportunistic circumstances by leveraging use of the odbcfetcharray function to access a certain...