When an invalid value is specified in the error message of custom fields in Atlassian Jira before version 7.6.6, from version 7.7.0 before version 7.7.4, from version 7.8.0 before version 7.8.4, and from version 7.9.0 before version 7.9.2, a cross site scripting (XSS) vulnerability in the issue collector allows remote attackers to inject arbitrary HTML or JavaScript.