Schneider Electric InduSoft Web Studio before 7.1.3.4 SP3 Patch 4 and InTouch Machine Edition 2014 before 7.1.3.4 SP3 Patch 4 provide an HMI user interface that lists all valid usernames, which makes it easier for remote attackers to obtain access via a brute-force password-guessing attack.
https://ics-cert.us-cert.gov/advisories/ICSA-15-085-01
http://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2015-054-02
http://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2015-054-01