PT-2022-16031 · Typo3 · Typo3/Html-Sanitizer
David Klein
·
Published
2022-12-13
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Updated
2022-12-16
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CVE-2022-23499
CVSS v3.1
6.1
Medium
| Vector | AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Name of the Vulnerable Software and Affected Versions
typo3/html-sanitizer versions prior to 1.5.0 or 2.1.1
Description
The HTML sanitizer is written in PHP and aims to provide XSS-safe markup based on explicitly allowed tags, attributes, and values. However, 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. 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. Only custom behaviors using one of those tag names were vulnerable to cross-site scripting.Recommendations
Update to version 1.5.0 or 2.1.1 to fix the issue.
As a temporary workaround, consider disabling custom behaviors that use the
script, style, noframes, noembed, or iframe tag names until a patch is available.
Restrict access to the vulnerable masterminds/html5 package to minimize the risk of exploitation.Exploit
Fix
XSS
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Weakness Enumeration
Related Identifiers
Affected Products
Typo3/Html-Sanitizer