CVE-2026-13051
Received Received - Intake

Locale::Maketext Template Injection in Form::Processor::Field::HtmlArea

Vulnerability report for CVE-2026-13051, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-08-13

Last updated on: 2026-08-13

Assigner: CPANSec

Description

Form::Processor::Field::HtmlArea versions from 0.06 through 1.162360 for Perl allow attacker selected method dispatch and resource exhaustion via an HTML::Tidy diagnostic that validate passes to add_error as a Locale::Maketext template. validate runs HTML::Tidy over the submitted markup and passes each resulting message to add_error as its first argument, which add_error hands to the language handle as the Locale::Maketext message key. The default handle's lexicon sets `_AUTO`, so a message that is not a lexicon entry is compiled as a bracket notation template instead of being looked up. Tidy diagnostics quote the offending attribute name or value, so a bracket group in the submitted markup reaches the template position, where the first token of the group names a method called on the language handle and the remaining tokens are its arguments. A group such as `[0]` makes the compile croak, and neither the field nor the handle catches it, so the exception leaves validate. `[sprintf,%2000000000d,7]` reaches CORE::sprintf with an attacker chosen field width. One submission of crafted markup to an HtmlArea field throws an unhandled exception out of form validation or allocates an arbitrary amount of memory, and an application whose language handle subclass defines side effecting public methods makes those callable with attacker chosen arguments. The other field types pass fixed templates with the submitted value in an argument slot, where it stays inert, and are unaffected.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-13
Last Modified
2026-08-13
Generated
2026-08-13
AI Q&A
2026-08-13
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
hank form_processor From 0.06 (inc) to 1.162360 (inc)

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-470 The product uses external input with reflection to select which classes or code to use, but it does not sufficiently prevent the input from selecting improper classes or code.
CWE-1336 The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This vulnerability affects the Form::Processor::Field::HtmlArea Perl module versions 0.06 through 1.162360. It allows attackers to exploit HTML::Tidy's diagnostic messages during validation. The module passes these messages to add_error as Locale::Maketext format strings. Since unrecognized messages are compiled as bracket notation, attacker-controlled markup can execute arbitrary code or cause resource exhaustion.

Detection Guidance

To detect this vulnerability, check if your system uses Form::Processor::Field::HtmlArea versions between 0.06 and 1.162360 for Perl. Inspect Perl module installations with commands like 'cpan -D Form::Processor' or 'perl -MForm::Processor -e "print $Form::Processor::VERSION"'. Look for HTML::Tidy integration in form validation processes.

Impact Analysis

An attacker could submit crafted HTML markup to an HtmlArea field, causing an unhandled exception that crashes form validation or allocates excessive memory. If the language handle subclass has side-effecting methods, those could be called with attacker-chosen arguments, potentially leading to code execution or denial of service.

Mitigation Strategies

Apply the official patch from Resource 2 which changes error handling in the validate method. Update Form::Processor to version 1.162360 or later. If immediate patching is not possible, disable HtmlArea fields or restrict user input to trusted sources until patched.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-13051. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart