Release Date: December 18, 2017
Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.
Affected Versions: version 8.8.0
Vulnerability Type: Authentication Bypass
Severity: Critical
Suggested CVSS v3.0: AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N/E:F/RL:O/RC:C (What's that?)
CVE: not assigned yet
Problem Description: The extension is vulnerable to Authentication Bypass. Frontend users can be authenticated by only knowing their username.
Solution: An updated version 8.8.1 is available from the TYPO3 Extension Manager and at https://extensions.typo3.org/extension/download/sf_register/8.8.1/zip/. Users of the extension are advised to update the extension as soon as possible.
Credits: Credits go to Manuel Glauser and Sebastian Müller 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.