CVE-2021-21365
5.4 · MEDIUMOverview
CVE-2021-21365 is a medium-severity vulnerability affecting typo3 typo3. It was published on April 27, 2021 and has a CVSS 3.1 base score of 5.4 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
Bootstrap Package is a theme for TYPO3. It has been discovered that rendering content in the website frontend is vulnerable to cross-site scripting. A valid backend user account is needed to exploit this vulnerability. Users of the extension, who have overwritten the affected templates with custom code must manually apply the security fix. Update to version 7.1.2, 8.0.8, 9.1.4, 10.0.10 or 11.0.3 of the Bootstrap Package that fix the problem described. Updated version are available from the TYPO3 extension manager, Packagist and at https://extensions.typo3.org/extension/download/bootstrap_package/.
Remediation
Check the references section for vendor advisories and patches from typo3. Update typo3 to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| typo3 | typo3 | >= 0, < 7.1.2 | Affected |
References
Frequently Asked Questions
What is CVE-2021-21365?
CVE-2021-21365 is a medium-severity vulnerability affecting typo3 typo3. It was published on April 27, 2021 and has a CVSS 3.1 base score of 5.4 (MEDIUM).
How severe is CVE-2021-21365?
This vulnerability has a CVSS 3.1 base score of 5.4, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2021-21365?
Check the references section for vendor advisories and patches from typo3. Update typo3 to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-21365?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-21365 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
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