CVE-2021-39307: Pdftron Webviewer UI

Medium severity, CVSS 6.1. EPSS: 1.1% chance of exploitation in the next 30 days.

PDFTron's WebViewer UI 8.0 or below renders dangerous URLs as hyperlinks in supported documents, including JavaScript URLs, allowing the execution of arbitrary JavaScript code.

Affected products

• Pdftron Webviewer UI: up to and including 8.0

Published 2021-09-15. Last modified 2026-06-17.