* SECURITY UPDATE: denial of service via double free in vba processing - libclamav/vba_extract.c: set buf to NULL when it gets freed. - http://git.clamav.net/gitweb?p=clamav-devel.git;a=commit;h=d21fb8d975f8c9688894a8cef4d50d977022e09f - CVE-2011-1003