vulnerability-lookup 2.16.0 allows XSS in bundle.py, comment.py, and user.py, by a user on a vulnerability-lookup instance who can add bundles, comments, or sightings. A cross-site scripting (XSS) vulnerability was discovered in the handling of user-supplied input in the Bundles, Comments, and Sightings components. Untrusted data was not properly sanitized before being rendered in templates and tables, which could allow attackers to inject arbitrary JavaScript into the application. The issue was due to unsafe use of innerHTML and insufficient validation of dynamic URLs and model fields. This vulnerability has been fixed by escaping untrusted data, replacing innerHTML assignments with safer DOM methods, encoding URLs with encodeURIComponent, and improving input validation in the affected models.