Symantec LiveUpdate before 1.6 does not use cryptography to ensure the integrity of download files, which allows remote attackers to execute arbitrary code via DNS spoofing of the update.symantec.com site.
https://exchange.xforce.ibmcloud.com/vulnerabilities/7235
https://euvd.enisa.europa.eu/vulnerability/EUVD-2001-1106
http://www.securityfocus.com/bid/3403
http://www.securityfocus.com/archive/1/218717
http://www.sarc.com/avcenter/security/Content/2001.10.05.html