Summary
Out-of-bounds Write in zlib affects Nokogiri
Nokogiri v1.13.4 updates the vendored zlib from 1.2.11 to 1.2.12, which addresses CVE-2018-25032. That CVE is scored as CVSS 7.4 "High" on the NVD record as of 2022-04-05.
Please note that this advisory only applies to the CRuby implementation of Nokogiri < 1.13.4, and only if the packaged version of zlib is being used. Please see this document for a complete description of which platform gems vendor zlib. If you've overridden defaults at installation time to use system libraries instead of packaged libraries, you should instead pay attention to your distro's zlib release announcements.
Mitigation
Upgrade to Nokogiri >= v1.13.4.
CVE-2018-25032 in zlib
- Severity: High
- Type: CWE-787 Out of bounds write
- Description: zlib before 1.2.12 allows memory corruption when deflating (i.e., when compressing) if the input has many distant matches.
Impact
A write operation targets a memory location beyond the intended buffer boundary. Typical impact: memory corruption, crash, or arbitrary code execution.
GHSA-V6GP-9MMM-C6P5 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 (1.13.4); 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.
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Frequently Asked Questions
- What is GHSA-V6GP-9MMM-C6P5? GHSA-V6GP-9MMM-C6P5 is a high-severity out-of-bounds write vulnerability in nokogiri (rubygems), affecting versions < 1.13.4. It is fixed in 1.13.4. A write operation targets a memory location beyond the intended buffer boundary.
- How severe is GHSA-V6GP-9MMM-C6P5? GHSA-V6GP-9MMM-C6P5 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 GHSA-V6GP-9MMM-C6P5? nokogiri (rubygems) versions < 1.13.4 is affected.
- Is there a fix for GHSA-V6GP-9MMM-C6P5? Yes. GHSA-V6GP-9MMM-C6P5 is fixed in 1.13.4. Upgrade to this version or later.
- Is GHSA-V6GP-9MMM-C6P5 exploitable, and should I be worried? Whether GHSA-V6GP-9MMM-C6P5 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 GHSA-V6GP-9MMM-C6P5 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 GHSA-V6GP-9MMM-C6P5? Upgrade
nokogirito 1.13.4 or later.