CVE-2022-0759 — kubeclient
HIGHCVE-2022-0759 is a high-severity (CVSS 8.1) CWE-295 vulnerability in kubeclient. A fix is available for kubeclient — see the affected versions and patch details below.
Improper Certificate Validation in kubeclient
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2022-0759 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
kubeclientReal-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
A flaw was found in all versions of kubeclient up to (but not including) v4.9.3, the Ruby client for Kubernetes REST API, in the way it parsed kubeconfig files. When the kubeconfig file does not configure custom CA to verify certs, kubeclient ends up accepting any certificate (it wrongly returns VERIFY_NONE). Ruby applications that leverage kubeclient to parse kubeconfig files are susceptible to Man-in-the-middle attacks (MITM).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | kubeclient | all versions | 4.9.3bundle update kubeclient --conservative |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for kubeclient, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update kubeclient to 4.9.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-0759 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2022-0759 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-0759. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
| Product | Fixed in | Advisory |
|---|---|---|
| Logging subsystem for Red Hat OpenShift 5.4 | openshift-logging/fluentd-rhel8:v1.14.5-3 | RHSA-2022:1461 |
| OpenShift Logging 5.2 | openshift-logging/fluentd-rhel8:v1.7.4-176 | RHSA-2022:2218 |
| OpenShift Logging 5.3 | openshift-logging/fluentd-rhel8:v1.7.4-178 | RHSA-2022:2217 |
| Red Hat Satellite 6.14 for RHEL 8 | tfm-rubygem-kubeclient-0:4.10.1-1.el8sat | RHSA-2023:6818 |
| RHOL-5.5-RHEL-8 | openshift-logging/fluentd-rhel8:v1.14.6-29 | RHSA-2022:6051 |
Frequently Asked Questions
Is CVE-2022-0759 in your dependencies?
O3 Security finds CVE-2022-0759 across RubyGems dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.