TYPO3-EXT-SA-2020-012: Cross-Site Scripting in extension "Google reCAPTCHA (v2/v3)" (jh_captcha)

Categories: Development, Security Created by Torben Hansen
It has been discovered that the extension "Google reCAPTCHA (v2/v3)" (jh_captcha) is susceptible to Cross-Site Scripting.
  • Release Date: July 07, 2020
  • Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.
  • Component: Google reCAPTCHA (v2/v3) (jh_captcha)
  • Vulnerability Type: Cross-Site Scripting
  • Affected Versions: 3.0.2 - 3.0.0 and 2.1.3 and below
  • Severity: Medium
  • Suggested CVSS v3.1: AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C
  • References: CVE-2020-15514

Problem Description

The extension fails to properly encode user input for output in HTML context. The issue is only exploitable by backend users with access to TypoScript settings of the extension.


Updated versions 2.1.4 and 3.0.3 are available from the TYPO3 extension manager, Packagist and at
Users of the extension are advised to update the extension as soon as possible.


Thanks to Sven Jürgens  for discovering and reporting the vulnerability and to Jan Haffner for providing an updated version of the extension.

General Advice

Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.