How severe is CVE-2022-23499?

CVE-2022-23499 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2022-23499?

CVE-2022-23499 affects the following packages: typo3/html-sanitizer (Packagist), typo3/html-sanitizer (Packagist), typo3/cms (Packagist), typo3/cms (Packagist), typo3/cms (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2022-23499?

Update typo3/html-sanitizer to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-23499 is resolved across your whole dependency graph.

How do I detect CVE-2022-23499 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/html-sanitizer. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2022-23499 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2022-23499?

O3 pinpoints whether CVE-2022-23499 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2022-23499 actively exploited in the wild?

No public exploit code has been indexed for CVE-2022-23499 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2022-23499?

CVE-2022-23499 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 35th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2022-23499?

CVE-2022-23499 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2022-23499 published, and has it been updated?

CVE-2022-23499 was published on December 13, 2022 and was last updated on March 14, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

CVE-2022-23499

MEDIUM

Cross-Site Scripting Protection bypass in HTML Sanitizer

Also known asGHSA-hvwx-qh2h-xcfj

Published

Dec 13, 2022

Updated

Mar 14, 2026

Affected

5 pkgs

Patched

5 / 5

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk35th percentile+0.20%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

5 pkgs affected

🐘typo3/html-sanitizer🐘typo3/html-sanitizer🐘typo3/cms🐘typo3/cms🐘typo3/cms

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

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.

Affected Packages

5 total 5 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`typo3/html-sanitizer`	≥ 1.0.0&&< 1.5.0	1.5.0
🐘Packagist	`typo3/html-sanitizer`	≥ 2.0.0&&< 2.1.1	2.1.1
🐘Packagist	`typo3/cms`	≥ 10.0.0&&< 10.4.33	10.4.33
🐘Packagist	`typo3/cms`	≥ 11.0.0&&< 11.5.20	11.5.20
🐘Packagist	`typo3/cms`	≥ 12.0.0&&< 12.1.1	12.1.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/html-sanitizer. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update typo3/html-sanitizer to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-23499 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2022-23499 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2022-23499. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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 fur

O3 Security · Impact-Aware SCA

Is CVE-2022-23499 in your dependencies?

O3 detects CVE-2022-23499 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works