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://advisories.mageia.org/MGASA-2014-0406.html
http://lists.fedoraproject.org/pipermail/package-announce/2014-September/139441.html
http://packetstormsecurity.com/files/128422/Perl-5.20.1-Deep-Recursion-Stack-Overflow.html
http://seclists.org/fulldisclosure/2014/Sep/84
http://seclists.org/oss-sec/2014/q3/692
http://secunia.com/advisories/61441
http://secunia.com/advisories/61961
https://exchange.xforce.ibmcloud.com/vulnerabilities/96216
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05240731
http://www.mandriva.com/security/advisories?name=MDVSA-2015:136