How severe is GHSA-wx95-c6cv-8532?

GHSA-wx95-c6cv-8532 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-wx95-c6cv-8532?

GHSA-wx95-c6cv-8532 affects the following packages: nokogiri (RubyGems). Ecosystems affected: RubyGems.

How do I fix GHSA-wx95-c6cv-8532?

Update nokogiri to 1.19.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wx95-c6cv-8532 is resolved across your whole dependency graph.

How do I detect GHSA-wx95-c6cv-8532 in my RubyGems dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nokogiri. 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 GHSA-wx95-c6cv-8532 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 GHSA-wx95-c6cv-8532?

O3 pinpoints whether GHSA-wx95-c6cv-8532 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 GHSA-wx95-c6cv-8532 actively exploited in the wild?

No public exploit code has been indexed for GHSA-wx95-c6cv-8532 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.

When was GHSA-wx95-c6cv-8532 published, and has it been updated?

GHSA-wx95-c6cv-8532 was published on February 18, 2026 and was last updated on February 25, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

💎 RubyGems

GHSA-wx95-c6cv-8532

MEDIUM

Nokogiri does not check the return value from xmlC14NExecute

Published

Feb 18, 2026

Updated

Feb 25, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Blast Radius

1 pkg affected

💎nokogiri

Real-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

Nokogiri's CRuby extension fails to check the return value from xmlC14NExecute in the method Nokogiri::XML::Document#canonicalize and Nokogiri::XML::Node#canonicalize. When canonicalization fails, an empty string is returned instead of raising an exception. This incorrect return value may allow downstream libraries to accept invalid or incomplete canonicalized XML, which has been demonstrated to enable signature validation bypass in SAML libraries.

JRuby is not affected, as the Java implementation correctly raises RuntimeError on canonicalization failure.

Mitigation

Upgrade to Nokogiri >= 1.19.1.

Severity

The maintainers have assessed this as Medium severity. Nokogiri itself is a parsing library without a clear security boundary related to canonicalization, so the direct impact is that a method returns incorrect data on invalid input. However, this behavior was exploited in practice to bypass SAML signature validation in downstream libraries (see References).

Credit

This vulnerability was responsibly reported by HackerOne researcher d4d.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
💎RubyGems	`nokogiri`	≥ 1.5.1&&< 1.19.1	1.19.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nokogiri. 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 nokogiri to 1.19.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wx95-c6cv-8532 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-wx95-c6cv-8532 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-wx95-c6cv-8532. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

## Summary Nokogiri's CRuby extension fails to check the return value from `xmlC14NExecute` in the method `Nokogiri::XML::Document#canonicalize` and `Nokogiri::XML::Node#canonicalize`. When canonicalization fails, an empty string is returned instead of raising an exception. This incorrect return value may allow downstream libraries to accept invalid or incomplete canonicalized XML, which has been demonstrated to enable signature validation bypass in SAML libraries. JRuby is not affected, as the Java implementation correctly raises `RuntimeError` on canonicalization failure. ## Mitigation U

O3 Security · Impact-Aware SCA

Is GHSA-wx95-c6cv-8532 in your dependencies?

O3 detects GHSA-wx95-c6cv-8532 across RubyGems 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