** DISPUTED ** Atlassian Crowd 2.6.3 allows remote attackers to execute arbitrary commands via unspecified vectors related to a \symmetric backdoor.\ NOTE: as of 20130704 the vendor could not reproduce the issue stating \We've been unable to substantiate the existence of CVE-2013-3926. The author of the article has not contacted Atlassian and has provided no detail making it difficult to validate the claim... If we can confirm that there is a vulnerability a patch will be issued.\