GitLab Community and Enterprise Editions version 9.2 up to 10.4 are vulnerable to XSS because a lack of input validation in the milestones …

GitLab Community and Enterprise Editions version 9.2 up to 10.4 are vulnerable to XSS because a lack of input validation in the milestones component leads to cross site scripting (specifically, data-milestone-id in the milestone dropdown feature). This is fixed in 10.6.3, 10.5.7, and 10.4.7.