Summary
Nokogiri 1.13.8, 1.13.9 fails to check the return value from xmlTextReaderExpand in the method Nokogiri::XML::Reader#attribute_hash. This can lead to a null pointer exception when invalid markup is being parsed.
For applications using XML::Reader to parse untrusted inputs, this may potentially be a vector for a denial of service attack.
Mitigation
Upgrade to Nokogiri >= 1.13.10.
Users may be able to search their code for calls to either XML::Reader#attributes or XML::Reader#attribute_hash to determine if they are affected.
Severity
The Nokogiri maintainers have evaluated this as High Severity 7.5 (CVSS3.1).
References
Credit
This vulnerability was responsibly reported by @davidwilemski.
Impact
The application dereferences a null pointer, causing a crash. Typical impact: denial of service via crash.
CVE-2022-23476 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.13.10); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2022-23476? CVE-2022-23476 is a high-severity null pointer dereference vulnerability in nokogiri (rubygems), affecting versions >= 1.13.8, < 1.13.10. It is fixed in 1.13.10. The application dereferences a null pointer, causing a crash.
- How severe is CVE-2022-23476? CVE-2022-23476 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of nokogiri are affected by CVE-2022-23476? nokogiri (rubygems) versions >= 1.13.8, < 1.13.10 is affected.
- Is there a fix for CVE-2022-23476? Yes. CVE-2022-23476 is fixed in 1.13.10. Upgrade to this version or later.
- Is CVE-2022-23476 exploitable, and should I be worried? Whether CVE-2022-23476 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2022-23476 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2022-23476? Upgrade
nokogirito 1.13.10 or later.