How severe is GHSA-wfpw-mmfh-qq69?

No CVSS score has been assigned to GHSA-wfpw-mmfh-qq69 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-wfpw-mmfh-qq69?

GHSA-wfpw-mmfh-qq69 affects the following packages: nokogiri (RubyGems). Ecosystems affected: RubyGems.

How do I fix GHSA-wfpw-mmfh-qq69?

Update nokogiri to 1.19.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wfpw-mmfh-qq69 is resolved across your whole dependency graph.

How do I detect GHSA-wfpw-mmfh-qq69 in my RubyGems dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nokogiri, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-wfpw-mmfh-qq69 if there is no patch (or I can't update yet)?

Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.

Is GHSA-wfpw-mmfh-qq69 actively exploited in the wild?

No public exploit code has been indexed for GHSA-wfpw-mmfh-qq69 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 GHSA-wfpw-mmfh-qq69?

GHSA-wfpw-mmfh-qq69 has an EPSS (Exploit Prediction Scoring System) score of 0.1%, placing it in the 2th 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 GHSA-wfpw-mmfh-qq69?

GHSA-wfpw-mmfh-qq69 is classified as Use After Free (CWE-416). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-wfpw-mmfh-qq69 published, and has it been updated?

GHSA-wfpw-mmfh-qq69 was published on June 19, 2026 and was last updated on September 10, 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

Not in CISA KEV

Nokogiri: Possible Use-After-Free in XInclude ProcessingGHSA-wfpw-mmfh-qq69

GHSA-wfpw-mmfh-qq69 is a Use After Free vulnerability in nokogiri. A fix is available for nokogiri — see the affected versions and patch details below.

Also known asCVE-2026-57438

Published

Jun 19, 2026

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 25, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-wfpw-mmfh-qq69.

EPSS Exploitation Probability

via FIRST.org ↗

0.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs2th percentile — riskier than 2% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

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

XInclude substitution performed by Nokogiri::XML::Node#do_xinclude replaced each <xi:include> in place, freeing the include node along with its children (such as <xi:fallback> and its descendants) and any namespaces declared on them. If an application had already exposed one of those nodes or namespaces to Ruby, the corresponding Ruby object was left pointing at freed memory. Using the object could result in invalid reads or writes to memory.

Nokogiri 1.19.4 substitutes each <xi:include> on a defensive copy by default, so the structures libxml2 frees are never the ones bound to live Ruby objects.

Only the CRuby implementation is affected; JRuby is not affected.

Severity

The Nokogiri maintainers have evaluated this as low severity. Reaching it requires an unusual API-usage pattern that does not arise during normal use. The application must parse a document without XInclude, traverse into an <xi:include> subtree to expose its nodes or namespaces to Ruby, and only then invoke XInclude processing. The common case, requesting XInclude at parse time, operates on a freshly parsed document whose nodes are not yet exposed to Ruby and is not affected. Nokogiri 1.19.4 makes this pattern safe by default and requires no change to application code.

Mitigation

Upgrade to Nokogiri 1.19.4 or later.

As a workaround for earlier versions, perform XInclude substitution at parse time (with the xinclude parse option) rather than calling #do_xinclude on a document that has already been traversed. A freshly parsed document has no nodes exposed to Ruby, so the substitution is safe.

Credit

This issue was responsibly reported by Zheng Yu from depthfirst.com.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
💎RubyGems	`nokogiri`	all versions	1.19.4`bundle update nokogiri --conservative`

Affected Products

1 product · 1 configurations

Application

nokogirinokogiri

< 1.19.4

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nokogiri, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update nokogiri to 1.19.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wfpw-mmfh-qq69 is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

A flaw was found in Nokogiri, an XML and HTML library for the Ruby programming language. When performing XInclude substitution via Nokogiri::XML::Node#do_xinclude, the library frees memory associated with replaced xi:include nodes, their children (including xi:fallback), and declared namespaces. If an application has…

Workaround published by Red Hat

Upgrade to Nokogiri 1.19.4 or later. As a workaround for earlier versions, perform XInclude substitution at parse time (with the xinclude parse option) rather than calling #do_xinclude on a document that has already been traversed. A freshly parsed document has no nodes exposed to Ruby, so the substitution is safe.

Source: Red Hat security advisory for GHSA-wfpw-mmfh-qq69 (CC BY 4.0)

Frequently Asked Questions

### Summary XInclude substitution performed by `Nokogiri::XML::Node#do_xinclude` replaced each `<xi:include>` in place, freeing the include node along with its children (such as `<xi:fallback>` and its descendants) and any namespaces declared on them. If an application had already exposed one of those nodes or namespaces to Ruby, the corresponding Ruby object was left pointing at freed memory. Using the object could result in invalid reads or writes to memory. Nokogiri 1.19.4 substitutes each `<xi:include>` on a defensive copy by default, so the structures libxml2 frees are never the ones bo

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