Path Traversal in TYPO3
CVE-2021-21357
TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 8.7.40, 9.5.25, 10.4.14, 11.1.1 due to improper input validation, attackers can by-pass restrictions of predefined options and submit arbitrary data in the Form Designer backend module of the Form Framework. In the default configuration of the Form Framework this allows attackers to explicitly allow arbitrary mime-types for file uploads - however, default _fileDenyPattern_ successfully blocked files like _.htaccess_ or _malicious.php_. Besides that, attackers can persist those files in any writable directory of the corresponding TYPO3 installation. A valid backend user account with access to the form module is needed to exploit this vulnerability. This is fixed in versions 8.7.40, 9.5.25, 10.4.14, 11.1.1.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H.
EPSS exploit prediction
EPSS: 0.016 (74.9th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 74.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000
Affected products
- TYPO3
- TYPO3 Typo3.cms — versions >= 8.0.0, <= 8.7.39, >= 9.0.0, <= 9.5.24, >= 10.0.0, <= 10.4.13
Weakness classification (CWE)
References
- packagist.org/packages/typo3/cms-form (Third Party Advisory, Release Notes)
- github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-3vg7-jw9m-pc3f (Third Party Advisory)
- typo3.org/security/advisory/typo3-core-sa-2021-003 (Vendor Advisory)
Frequently asked questions
- What is CVE-2021-21357?
- CVE-2021-21357 is a high-severity vulnerability in TYPO3, classified under Improper Input Validation. CVSS score: 8.3/10. Published 2021-03-23.
- How severe is CVE-2021-21357?
- High severity. CVSS v3 base score is 8.3 out of 10.