TYPO3-CORE-SA-2015-009: Non-Persistent Cross-Site Scripting

Categories: TYPO3 CMS Created by Helmut Hummel
It has been discovered, that TYPO3 is susceptible to Non-Persistent Cross-Site Scripting

Component Type: TYPO3 CMS

Release Date: September 8, 2015

Vulnerable subcomponent: Backend

Vulnerability Type: Cross-Site Scripting

Affected Versions: Versions 6.2.0 to 6.2.14, 7.0.0 to 7.3.0

Severity: Low

Suggested CVSS v2.0: AV:N/AC:M/Au:S/C:P/I:P/A:N/E:F/RL:OF/RC:C

CVE: CVE-2015-5956

Problem Description: It has been discovered, that it is possible to forge a link to a backend module, which contains a JavaScript payload. This JavaScript is executed, if an authenticated editor with access to the module follows the link and after that, is tricked to click on a certain HTML target. Because TYPO3 versions 7.4.0 and above include a secret token unknown to an attacker in every URL, an exploit would not be feasible for these versions.

Solution: Update to TYPO3 versions 6.2.15 or 7.4.0 that fix the problem described.

Credits: Thanks to Julien Ahrens (secunet Security Networks AG) who discovered and reported 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 on our review system.