Jira Data Center, Jira Core Data Center, Jira Software Data Center, and Jira Service Management Data Center exposed a Ehcache RMI network service which attackers, who can connect to the service, on port 40001 and potentially 40011, could execute arbitrary code of their choice in Jira through deserialization due to a missing authentication vulnerability. While Atlassian strongly suggests restricting access to the Ehcache ports to only Data Center instances, fixed versions of Jira will now require a shared secret in order to allow access to the Ehcache service. Various versions of Jira Data Center, Jira Core Data Center, Jira Software Data Center, and Jira Service Management Data Center are affected.
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