Release Date: November 07, 2017
Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.
Affected Versions: version 2.4.0 and below
Vulnerability Type: Cross-Site Scripting
Severity: Low
Suggested CVSS v3.0: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:F/RL:O/RC:C (What's that?)
CVE: not assigned yet
Problem Description: The extension fails to properly encode user input for output in HTML context.
Solution: An updated version 2.4.1 is available from the TYPO3 Extension Manager and at https://extensions.typo3.org/extension/download/formhandler/2.4.1/zip/. Users of the extension are advised to update the extension as soon as possible.
Credits: Credits go to Till Maas who discovered and reported the vulnerability.
General advice: Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list to receive future Security Bulletins via E-mail.