Multiple buffer overflows in PHP before 5.2.1 allow attackers to cause a denial of service and possibly execute arbitrary code via unspecified vectors in the (1) session (2) zip (3) imap and (4) sqlite extensions; (5) stream filters; and the (6) str_replace (7) mail (8) ibase_delete_user (9) ibase_add_user and (10) ibase_modify_user functions. NOTE: vector 6 might actually be an integer overflow (CVE-2007-1885). NOTE: as of 20070411 vector (3) might involve the imap_mail_compose function (CVE-2007-1825).