GHSA-9j5w-2cqc-cwj9 Magento LTS vulnerable to Stored XSS via TinyMCE WYSIWYG Editor

• Packagist openmage/magento-lts: < 20.2.0 → fixed in 20.2.0

From HackerOne report #1948040 by Halit AKAYDIN (hltakydn) Impact _What kind of vulnerability is it? Who is impacted?_ The TinyMCE WYSIWYG editor fails to filter scripts when rendering the HTML in specially crafted HTML tags. Patches _Has the problem been patched? What versions should users upgrade to?_ This vulnerability was fixed in version 20.2.0 by upgrading TinyMCE to a recent version in https://github.com/OpenMage/magento-lts/pull/3220 Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ The WYSIWYG editor features could be disabled in the configuration. Possibly some WAF appliances would filter this attack. References _Are there any links users can visit to find out more?_ The attack is simply an exploit of the "onmouseover" attribute of an `img` element as described on OWASP XSS Filter Evasion