CSRF in Typo3

CVE-2021-41113

TYPO3 is an open source PHP based web content management system released under the GNU GPL. It has been discovered that the new TYPO3 v11 feature that allows users to create and share deep links in the backend user interface is vulnerable to cross-site-request-forgery. The impact is the same as described in TYPO3-CORE-SA-2020-006 (CVE-2020-11069). However, it is not limited to the same site context and does not require the attacker to be authenticated. In a worst case scenario, the attacker could create a new admin user account to compromise the system. To successfully carry out an attack, an attacker must trick his victim to access a compromised system. The victim must have an active session in the TYPO3 backend at that time. The following Same-Site cookie settings in $GLOBALS[TYPO3_CONF_VARS][BE][cookieSameSite] are required for an attack to be successful: SameSite=strict: malicious evil.example.org invoking TYPO3 application at good.example.org and SameSite=lax or none: malicious evil.com invoking TYPO3 application at example.org. Update your instance to TYPO3 version 11.5.0 which addresses the problem described.

Vulnerability class: CSRF (Cross-Site Request Forgery)

EPSS: 0.006 (46.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

  • Typo3 — versions >= 11.2.0, < 11.5.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-41113?
CVE-2021-41113 is a high-severity vulnerability in Typo3, classified under Cross-Site Request Forgery (CSRF). CVSS score: 8.8/10. Published 2021-10-05.
How severe is CVE-2021-41113?
High severity. CVSS v3 base score is 8.8 out of 10.