CVE-2022-36020 Bypass of Cross-Site Scripting Protection in typo3/html-sanitizer
Attackers can bypass XSS protections in the TYPO3 HTML sanitizer library via malicious markup, requiring an upgrade to secure applications.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2022-36020?
CVE-2022-36020 is a medium-severity cross-site scripting vulnerability in TYPO3 html-sanitizer, published on 13 Sep 2022. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The typo3/html-sanitizer package is an HTML sanitizer, written in PHP, aiming to provide XSS-safe markup based on explicitly allowed tags, attributes and values. Due to a parsing issue in the upstream package `masterminds/html5`, malicious markup used in a sequence with special HTML comments cannot be filtered and sanitized. This allows for a bypass of the cross-site scripting mechanism of `typo3/html-sanitizer`. This issue has been addressed in versions 1.0.7 and 2.0.16 of the `typo3/html-sanitizer` package. Users are advised to upgrade. There are no known workarounds for this issue.
Weakness: CWE-79
Which versions are affected by CVE-2022-36020?
12 open source packages ship an affected version, including typo3/html-sanitizer, typo3/cms and typo3/cms-core. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
typo3/html-sanitizer Packagist | From 1.0.0 | 1.0.7 |
typo3/html-sanitizer Packagist | From 1.0.0 | 1.0.7 |
typo3/html-sanitizer Packagist | From 2.0.0 | 2.0.16 |
typo3/html-sanitizer Packagist | From 2.0.0 | 2.0.16 |
typo3/cms Packagist | From 10.0.0 | 10.4.32 |
typo3/cms Packagist | From 10.0.0 | 10.4.32 |
6 more packages
typo3/cms Packagist | From 11.0.0 | 11.5.16 |
typo3/cms Packagist | From 11.0.0 | 11.5.16 |
typo3/cms-core Packagist | From 10.0.0 | 10.4.32 |
typo3/cms-core Packagist | From 10.0.0 | 10.4.32 |
typo3/cms-core Packagist | From 11.0.0 | 11.5.16 |
typo3/cms-core Packagist | From 11.0.0 | 11.5.16 |
Products include Typo3 Html Sanitizer.
How do I fix CVE-2022-36020?
Upgrade typo3/html-sanitizer to a fixed version for your release line: 1.0.7 or 2.0.16.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2022-36020 being exploited?
There is no known exploitation of CVE-2022-36020 in the wild and no public exploit code.
Other vulnerabilities in TYPO3 html-sanitizer
Sources
Also known as GHSA-47m6-46mj-p235.