The resolution SAML SSO apps for Atlassian products allow a remote attacker to login to a user account when only the username is known (i.e., no other authentication is provided). The fixed versions are for Jira: 3.6.6.1, 4.0.12, 5.0.5; for Confluence 3.6.6, 4.0.12, 5.0.5; for Bitbucket 2.5.9, 3.6.6, 4.0.12, 5.0.5; for Bamboo 2.5.9, 3.6.6, 4.0.12, 5.0.5; and for Fisheye 2.5.9.

An issue was discovered in the SAML Single Sign On (SSO) plugin for several Atlassian products affecting versions 3.1.0 through 3.2.2 for Jira and Confluence, versions 2.4.0 through 3.0.3 for Bitbucket, and versions 2.4.0 through 2.5.2 for Bamboo. It allows locally disabled users to reactivate their accounts just by browsing the affected Jira/Confluence/Bitbucket/Bamboo instance, even when the applicable configuration option of the plugin has been disabled ("Reactivate inactive users"). Exploiting this vulnerability requires an attacker to be authorized by the identity provider and requires that the plugin's configuration option "User Update Method" have the "Update from SAML Attributes" value.