---
id: CVE-2026-120636
title: >-
  CGI versions before 5.00 for Perl allow open redirects and script injection
  via URLs built from REQUEST_URI in url and start_form
summary: >-
  CGI versions before 5.00 for Perl allow open redirects and script injection
  via URLs built from REQUEST_URI in url and start_form.


  url(-absolute=>1), url(-relative=>1) and the default start_form action are
  built from the client-supplied…
severity: none
cwe:
  - CWE-601
  - CWE-79
product: CGI
affected:
  - CGI < 5.00
published: '2026-11-03'
updated: '2026-11-03'
sourceUpdated: '2026-11-03T23:40:18.085Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-120636'
references:
  - url: 'https://metacpan.org/release/LEEJO/CGI-4.72/source/lib/CGI.pm'
  - url: 'https://metacpan.org/release/LEEJO/CGI-5.00/changes'
  - url: >-
      https://github.com/leejo/CGI.pm/commit/9405ef3909ee94991a3474167aa53b9051bd8765.patch
tags:
  - cve.org
epss: 0.00212
epssPercentile: 0.1163
ingestedAt: '2026-11-05T20:33:06.617Z'
---

## Overview

CGI versions before 5.00 for Perl allow open redirects and script injection via URLs built from REQUEST_URI in url and start_form.

url(-absolute=>1), url(-relative=>1) and the default start_form action are built from the client-supplied REQUEST_URI without validation. The result can be protocol-relative (//evil.example), absolute-form (http://evil.example/) or contain backslashes, and url(-relative=>1) can return a javascript: URL. Links and form posts built from these URLs can go to another host.

## Affected

- `CGI < 5.00`

## Remediation

Upgrade to CGI 5.00 or later.