/ 
HTML-FormFu-2.07
/ HTML::FormFu::Plugin
Security Advisories (1)
CVE-2026-19873 (2026-08-31)

HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements. When a Repeatable element has counter_name set, its process method reads the repeat count from the named query string parameter, checks only that it is a positive integer, and passes it to repeat, which deep-clones the element's child subtree once per iteration. Nothing caps the value, and no attribute lets an application impose a limit. The count is read on every request, before the form decides whether it was submitted, so a plain GET reaches the clone loop with no credentials, no session and no request body. Nesting multiplies: a Repeatable inside a Repeatable takes a counter at each level, so an outer and an inner value of 100 build 10,000 clones. Once the form is submitted, each cloned field's constraints scan the whole element tree in _find_field_value, so cost grows faster than linearly with the count. A single request exhausts memory and CPU. The latest release on CPAN is 2.07, from 2018. Version 2.08 exists only in the git repository.

NAME

HTML::FormFu::Plugin - base class for plugins

VERSION

version 2.07

DESCRIPTION

Plugins can be added to a form or any element to modify their behaviour. Some plugins should only be added to either a form, or an element, depending on their design.

METHODS

Plugins can override any of the following method stubs.

process

Only plugins added to a form or a field element inheriting from HTML::FormFu::Role::Element::Field will have their process method run.

For form plugins, is called during "process" in HTML::FormFu, before process is called on any elements.

For field plugins, is called during the field's process call.

pre_process

For form plugins, is called immediately after pre_process is run on the elements.

For element plugins, is called before pre_process is run on form plugins.

post_process

For form plugins, is called immediately before "process" in HTML::FormFu returns.

For element plugins, is called before post_process is run on form plugins.

render

Only plugins added to a form will have their render method run.

Is called during "render" in HTML::FormFu before the "render_method" in HTML::FormFu is called.

post_render

Only plugins added to a form will have their post_render method run.

Is called during "render" in HTML::FormFu immediately before "render" in HTML::FormFu return.

Is passed a reference to the return value of "render_method" in HTML::FormFu.

CORE PLUGINS

HTML::FormFu::Plugin::StashValid

AUTHOR

Carl Franks, cfranks@cpan.org

LICENSE

This library is free software, you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

Carl Franks <cpan@fireartist.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2018 by Carl Franks.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.