GHSA-fx6x-h9g4-56f8 — plugins
MEDIUMGHSA-fx6x-h9g4-56f8 is a medium-severity (CVSS 6) CWE-300 vulnerability in github.com/containernetworking/plugins. 2 public exploit references exist, so weaponization risk is real. A fix is available for github.com/containernetworking/plugins — see the affected versions and patch details below.
containernetworking/plugins vulnerable to MitM attacks
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
GHSA-fx6x-h9g4-56f8 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
github.com/containernetworking/pluginsReal-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
A vulnerability was found in all versions of containernetworking/plugins before version 0.8.6, that allows malicious containers in Kubernetes clusters to perform man-in-the-middle (MitM) attacks. A malicious container can exploit this flaw by sending rogue IPv6 router advertisements to the host or other containers, to redirect traffic to the malicious container.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/containernetworking/plugins | all versions | 0.8.6go get github.com/containernetworking/plugins@v0.8.6 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/containernetworking/plugins, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/containernetworking/plugins to 0.8.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fx6x-h9g4-56f8 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 GHSA-fx6x-h9g4-56f8 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-fx6x-h9g4-56f8. 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.
In OpenShift Container Platform 4, the default network plugin, OpenShift SDN, and OVN Kubernetes, do not forward IPv6 traffic, making this vulnerability not exploitable. The affected code from containernetworking/plugins is however still included in these plugins, hence this vulnerability is rated Low for both…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 7 Extras | containernetworking-plugins-0:0.8.3-3.el7_8 | RHSA-2020:2684 |
| Red Hat Enterprise Linux 8 | container-tools:rhel8-8030020200923153805.2a301c24 | RHSA-2020:4694 |
| Red Hat OpenShift Container Platform 4.2 | containernetworking-plugins-0:0.8.6-1.rhaos4.2.el7 | RHSA-2020:2592 |
| Red Hat OpenShift Container Platform 4.3 | containernetworking-plugins-0:0.8.6-1.rhaos4.3.el7 | RHSA-2020:2443 |
| Red Hat OpenShift Container Platform 4.4 | containernetworking-plugins-0:0.8.6-1.rhaos4.4.el7 | RHSA-2020:2403 |
| Red Hat OpenShift Container Platform 4.5 | openshift4/ose-multus-cni:v4.5.0-202007012112.p0 | RHSA-2020:2412 |
| Red Hat OpenShift Container Platform 4.7 | openshift4/ose-sdn-rhel8:v4.7.0-202102130115.p0 | RHSA-2020:5633 |
| RHEL-8-CNV-2.4 | container-native-virtualization/kubevirt-cpu-model-nfd-plugin:v2.4.0-17 | RHSA-2020:3194 |
Frequently Asked Questions
Is GHSA-fx6x-h9g4-56f8 in your dependencies?
O3 Security finds GHSA-fx6x-h9g4-56f8 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.