CVE-2022-23499: TYPO3-CORE-SA-2022-017: By-passing Cross-Site Scripting Protection in HTML Sanitizer
Problem Due to a parsing issue in the upstream package masterminds/html5, malicious markup used in a sequence with special HTML CDATA sections cannot be filtered and sanitized. This allows bypassing the cross-site scripting mechanism of typo3/html-sanitizer.
Besides that, the upstream package masterminds/html5 provides HTML raw text elements (script, style, noframes, noembed and iframe) as DOMText nodes, which were not processed and sanitized further. None of the mentioned elements were defined in the default builder configuration, that's why only custom behaviors, using one of those tag names, were vulnerable to cross-site scripting.
Solution Update to typo3/html-sanitizer versions 1.5.0 or 2.1.1 that fix the problem described.
Other sources
HTML sanitizer is written in PHP, aiming to provide XSS-safe markup based on explicitly allowed tags, attributes and values. In versions prior to 1.5.0 or 2.1.1, malicious markup used in a sequence with special HTML CDATA sections cannot be filtered and sanitized due to a parsing issue in the upstream package masterminds/html5. This allows bypassing the cross-site scripting mechanism of typo3/html-sanitizer. The upstream package masterminds/html5 provides HTML raw text elements (script, style, noframes, noembed and iframe) as DOMText nodes, which were not processed and sanitized further. None of the mentioned elements were defined in the default builder configuration, that's why only custom behaviors, using one of those tag names, were vulnerable to cross-site scripting. This issue has been fixed in versions 1.5.0 and 2.1.1.
— MITRE
TYPO3 HTML Sanitizer vulnerable to Cross-Site Scripting
— Packagist
TYPO3-CORE-SA-2022-017: By-passing Cross-Site Scripting Protection in HTML Sanitizer
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
composer/typo3/cms-coreto a version that resolves this vulnerability.Fixed in 10.4.33 - Upgrade
Upgrade
composer/typo3/cms-coreto a version that resolves this vulnerability.Fixed in 11.5.20 - Upgrade
Upgrade
composer/typo3/cms-coreto a version that resolves this vulnerability.Fixed in 12.1.1 - Upgrade
Upgrade
composer/typo3/html-sanitizerto a version that resolves this vulnerability.Fixed in 2.1.1 - Upgrade
Upgrade
composer/typo3/html-sanitizerto a version that resolves this vulnerability.Fixed in 1.5.0 - Upgrade
Upgrade
composer/typo3/cmsto a version that resolves this vulnerability.Fixed in 10.4.33 - Upgrade
Upgrade
composer/typo3/cmsto a version that resolves this vulnerability.Fixed in 11.5.20 - Upgrade
Upgrade
composer/typo3/cmsto a version that resolves this vulnerability.Fixed in 12.1.1 - Upgrade
Upgrade
typo3/html-sanitizerto a version that resolves this vulnerability.Fixed in 1.5.0
Event History
Frequently Asked Questions
What is CVE-2022-23499?
CVE-2022-23499 is a vulnerability that allows bypassing cross-site scripting (XSS) protection in the TYPO3 HTML Sanitizer.
How does CVE-2022-23499 impact TYPO3 CMS?
CVE-2022-23499 impacts TYPO3 CMS versions 10.0.0 to 10.4.33, 11.0.0 to 11.5.20, and 12.0.0 to 12.1.1 when using the HTML Sanitizer component.
What is the severity of CVE-2022-23499?
The severity of CVE-2022-23499 is medium with a CVSS score of 6.1.
How can I fix CVE-2022-23499 in TYPO3 CMS?
To fix CVE-2022-23499 in TYPO3 CMS, upgrade to version 10.4.34 or higher for TYPO3 CMS 10.x, upgrade to version 11.5.21 or higher for TYPO3 CMS 11.x, and upgrade to version 12.1.2 or higher for TYPO3 CMS 12.x.
Where can I find more information about CVE-2022-23499?
You can find more information about CVE-2022-23499 in the TYPO3 security advisory TYPO3-CORE-SA-2022-017.