CVE-2026-85485

HTML::FormHandler before version 0.410002 for Perl renders field attributes into HTML without escaping using the process_attrs method. Applications with fields or labels where attributes are built from data rather than literals may allow attacker-influenced text in attribute values, potentially overriding field attributes or embedding JavaScript in rendered pages.

HTML::FormHandler before version 0.410002 for Perl renders option group labels and radio button labels into HTML without escaping. The Select, RadioGroup, CheckboxGroup and HorizCheckboxGroup widgets render a group label unescaped, and RadioGroup also renders each radio button's own label unescaped. Applications whose option list is built from data may allow attacker-influenced text in a label, potentially overriding options or embedding JavaScript.

HTML::FormHandler before version 0.410000 for Perl allows cross-site scripting via a submitted value rendered unescaped in an error message. The wrappers and renderers that emit a form's errors interpolate the error string straight into HTML with no escaping. The no_match and not_allowed messages splice the submitted value into that string, and a failing type constraint puts the rejected value into the message. A network request submitting markup to such a field can cause script execution in the victim's context.

Vulnerability in HTML::FormHandler before version 0.410000 for Perl allows attacker-selected method dispatch and resource exhaustion. This occurs because _apply_actions and add_error use error message text built from request data as a Locale::Maketext bracket notation template, potentially leading to dangerous method calls or memory allocation.