• Component Type: TYPO3 CMS
• Subcomponent: Backend User Interface (ext:backend)
• Release Date: May 12, 2020
• Vulnerability Type: Insecure Deserialization
• Affected Versions: 9.0.0-9.5.16, 10.0.0-10.4.1
• Severity: High
• Suggested CVSS: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
• References: CVE-2020-11067, CWE-502

Problem Description

It has been discovered that backend user settings (in $BE_USER->uc) are vulnerable to insecure deserialization. In combination with vulnerabilities of 3rd party components this can lead to remote code execution. A valid backend user account is needed to exploit this vulnerability.

Solution

Update to TYPO3 versions 9.5.17 or 10.4.2 that fix the problem described.

Credits

Thanks to TYPO3 security team member Oliver Hader who reported and fixed the issue.

General Advice

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

General Note

All security related code changes are tagged so that you can easily look them up in our review system.