CVE-2026-85485: HTML::FormHandler versions before 0.410002 for Perl render some error messages into HTML without escaping
HTML::FormHandler versions before 0.410002 for Perl render some error messages into HTML without escaping.
The Table form layout and the Bootstrap 2 and 3 wrappers splice each error string straight into the surrounding markup. Version 0.410000, the fix for CVE-2026-19872, escaped the equivalent values in the other layouts and wrappers, and 0.410002 extended that to these three.
Error messages that contain attacker-influenced content such as rejected field values could embed JavaScript in rendered pages.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
HTML::FormHandler (Perl)to a version that resolves this vulnerability.Fixed in 0.410002 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch CVE-2026-19872
Event History
Frequently Asked Questions
Which deployments are exposed?
Deployments using HTML::FormHandler versions earlier than 0.410002 are exposed when they render validation errors through the Table form layout or the Bootstrap 2 or Bootstrap 3 wrappers. Other layouts and wrappers received equivalent escaping in version 0.410000.
What must an attacker control to exploit this?
An attacker needs to cause an error message to include attacker-influenced content, such as a rejected field value, and have that error rendered in an affected layout or wrapper. The unescaped content can then embed JavaScript in the resulting page.
How can I determine whether an application is affected?
Check the installed HTML::FormHandler version and identify whether the application uses the Table layout or Bootstrap 2 or 3 wrappers to display errors. Versions before 0.410002 using any of those rendering paths are affected.
What is the remediation?
Upgrade HTML::FormHandler to version 0.410002 or later. That release extends HTML escaping for error strings to the Table layout and Bootstrap 2 and 3 wrappers.