GHSA-v6gp-9mmm-c6p5
HIGHOut-of-bounds Write in zlib affects Nokogiri
Blast Radius
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Description
Summary
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.
Impact
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | nokogiri | all versions | 1.13.4 |
Detection & mitigation playbook
Open-source dependencyDetect
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 1.13.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v6gp-9mmm-c6p5 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-v6gp-9mmm-c6p5 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-v6gp-9mmm-c6p5. 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-v6gp-9mmm-c6p5 in your dependencies?
O3 detects GHSA-v6gp-9mmm-c6p5 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.