Bypassing Cross-Site Scripting Protection in TYPO3 HTML Sanitizer
Date: 2023-11
Affected: composer/typo3/html-sanitizer, composer/typo3/html-sanitizer
Attack vector: xss
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2023-47125
CWE: CWE-79
CVSS: 4.7 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N)

> ### CVSS: `CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C` (4.4) ### Problem DOM processing instructions are not handled correctly. This allows bypassing the cross-site scripting mechanism of [`typo3/html-sanitizer`](https://packagist.org/packages/typo3/html-sanitizer). ### Solution Update to `typo3/html-sanitizer` versions 1.5.3 or 2.1.4 that fix the problem described. ### Credits Thanks to Yaniv Nizry and Niels Dossche who reported this issue, and to TYPO3 core & security team member Oliver Hader who fixed the issue. ### References * [TYPO3-CORE-SA-2023-007](https://typo3.org/security/advisory/typo3-core-sa-2023-007) * [Context & Details at `masterminds/html5`](https://github.com/Masterminds/html5-php/issues/241)


Mitigations:

Architectural layers (MAESTRO):