CVE-2018-1002100 — kubernetes
MEDIUMCVE-2018-1002100 is a medium-severity (CVSS 5.5) Improper Input Validation vulnerability in k8s.io/kubernetes. A fix is available for k8s.io/kubernetes — see the affected versions and patch details below.
Kubernetes arbitrary file overwrite
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-2018-1002100 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 377,636 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
k8s.io/kubernetesReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
In Kubernetes versions 1.5.x, 1.6.x, 1.7.x, 1.8.x, and prior to version 1.9.6, the kubectl cp command insecurely handles tar data returned from the container, and can be caused to overwrite arbitrary local files.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | k8s.io/kubernetes | ≥ 1.5.0-alpha.0&&< 1.9.6 | 1.9.6go get k8s.io/kubernetes@v1.9.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for k8s.io/kubernetes, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update k8s.io/kubernetes to 1.9.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-1002100 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-2018-1002100 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2018-1002100. 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.
Kubernetes support is moving from Red Hat Enterprise Linux to OpenShift Container Platform. Kubernetes and its dependencies will no longer be updated through the Extras channel. Instead, the Red Hat customers are advised to use Red Hat's supported Kubernetes-based products such as Red Hat OpenShift Container Platform.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift Container Platform 3.9 | atomic-openshift-0:3.9.30-1.git.0.dec1ba7.el7 | RHBA-2018:1796 |
Frequently Asked Questions
Is CVE-2018-1002100 in your dependencies?
O3 Security finds CVE-2018-1002100 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.