CVE-2023-23627
MEDIUMCVE-2023-23627 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in sanitize. O3 Security confirms whether CVE-2023-23627 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Sanitize vulnerable to Cross-site Scripting via Improper neutralization of `noscript` element
Blast Radius
sanitizeReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Sanitize is an allowlist-based HTML and CSS sanitizer. Versions 5.0.0 and later, prior to 6.0.1, are vulnerable to Cross-site Scripting. When Sanitize is configured with a custom allowlist that allows noscript elements, attackers are able to include arbitrary HTML, resulting in XSS (cross-site scripting) or other undesired behavior when that HTML is rendered in a browser. The default configurations do not allow noscript elements and are not vulnerable. This issue only affects users who are using a custom config that adds noscript to the element allowlist. This issue has been patched in version 6.0.1. Users who are unable to upgrade can prevent this issue by using one of Sanitize's default configs or by ensuring that their custom config does not include noscript in the element allowlist.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | sanitize | ≥ 5.0.0&&< 6.0.1 | 6.0.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for sanitize. 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 sanitize to 6.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-23627 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-2023-23627 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-2023-23627. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-23627 in your dependencies?
O3 detects CVE-2023-23627 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.