GHSA-cj75-f6xr-r4g7
Rails HTML Sanitizers: Possible XSS vulnerability with certain configurations
Blast Radius
rails-html-sanitizerReal-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
Summary
There is a possible cross-site scripting vulnerability in rails-html-sanitizer when the sanitizer is configured to allow an SVG reference element such as <use>. See related GHSA-9wjq-cp2p-hrgf in Loofah, whose SVG local-reference logic rails-html-sanitizer mirrors.
- Versions affected:
>= 1.0.3, < 1.7.1 - Not affected:
< 1.0.3 - Fixed versions:
1.7.1
Impact
Rails::HTML::PermitScrubber restricts SVG reference elements in the SVG_ALLOW_LOCAL_HREF collection to local, same-document references, but that restriction covered only the xlink:href attribute. Browsers also accept a plain href attribute per the SVG 2 spec, and it was not restricted, so those elements could reference arbitrary external documents. SVG <use> can load and render external SVG content by reference, and if the referenced document is same-origin and contains scripts, it could execute in the context of the sanitized document. <feImage> can load external images, which can be used for tracking.
Applications are impacted only when the allowed tags are overridden to include one of these SVG reference elements, for example <use> or <feImage>. The default allowed tags do not include these SVG elements, so applications using the default configuration are not affected.
Workarounds
Remove the SVG reference elements (such as use and feImage) from the overridden allowed tags. Applications using the default allowed tags are not affected.
References
- GHSA-9wjq-cp2p-hrgf: SVG
hrefattribute bypasses local-reference restriction in Loofah - CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Credit
Found by maintainer Mike Dalessio during a security audit.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | rails-html-sanitizer | ≥ 1.0.3&&< 1.7.1 | 1.7.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rails-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 rails-html-sanitizer to 1.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-cj75-f6xr-r4g7 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 GHSA-cj75-f6xr-r4g7 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 GHSA-cj75-f6xr-r4g7. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-cj75-f6xr-r4g7 in your dependencies?
O3 detects GHSA-cj75-f6xr-r4g7 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.