The Dumper method in Data::Dumper before 2.154, as used in Perl 5.20.1 and earlier, allows context-dependent attackers to cause a denial of service (stack consumption and crash) via an Array-Reference with many nested Array-References, which triggers a large number of recursive calls to the DD_dump function. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-4330
