The phar_parse_metadata function in ext/phar/phar.c in PHP before 5.4.40, 5.5.x before 5.5.24, and 5.6.x before 5.6.8 allows remote attackers to cause a denial of service (heap metadata corruption) or possibly have unspecified other impact via a crafted tar archive. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3307