Jenkins TestLink Plugin 3.16 and earlier stores credentials unencrypted in its global configuration file on the Jenkins master where they can be viewed by users with access to the master file system.

A cross-site scripting vulnerability exists in Jenkins TestLink Plugin 2.12 and earlier in TestLinkBuildAction/summary.jelly and others that allow an attacker who can control e.g. TestLink report names to have Jenkins serve arbitrary HTML and JavaScript

TestLink before v.1.9.20 is vulnerable to Cross Site Scripting (XSS) via the pop-up on upload file. When uploading a file, the XSS payload can be entered into the file name.