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 products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | kubeclient | 4.9.3 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ruby-kubeclient | 4.9.3-1 | — |
| Debian 13 | ruby-kubeclient | 4.9.3-1 | — |
| Debian 12 | ruby-kubeclient | 4.9.3-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | ruby-kubeclient | No fix yet | — |
| Ubuntu 26.04 LTS | ruby-kubeclient | No fix yet | — |
| Ubuntu 25.10 | ruby-kubeclient | No fix yet | — |
| Ubuntu 24.04 LTS | ruby-kubeclient | No fix yet | — |
| Ubuntu 22.04 LTS | ruby-kubeclient | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | ruby-kubeclient | No fix yet | — |
| Ubuntu 18.04 LTS | ruby-kubeclient | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Satellite Utils 6 | foreman +1 | 3.7.0.9-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | foreman +1 | 3.7.0.9-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | puppet-agent | 7.26.0-3.el8sat | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | puppetserver | 7.11.0-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | python-django +1 | 3.2.21-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | python-future +1 | 0.18.3-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | python-gitpython +1 | 3.1.32-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | python-pulp-ansible +1 | 1:0.16.0-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | python-requests +1 | 2.31.0-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | python-sqlparse +1 | 0.4.4-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite Capsule 6 | rubygem-rack | 2.2.7-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | foreman +13 | 3.7.0.9-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | puppet-agent | 7.26.0-3.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | puppetserver | 7.11.0-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | python-django +1 | 3.2.21-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite 6 | python-future +1 | 0.18.3-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite 6 | python-gitpython +1 | 3.1.32-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite 6 | python-pulp-ansible +1 | 1:0.16.0-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite 6 | python-requests +1 | 2.31.0-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite 6 | python-sqlparse +1 | 0.4.4-1.el8pc | RHSA-2023:6818 |
| Red Hat Satellite 6 | rubygem-actionpack +2 | 6.1.7.3-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | rubygem-git | 1.18.0-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | rubygem-globalid | 1.1.0-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | rubygem-kubeclient | 4.10.1-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | rubygem-rack | 2.2.7-1.el8sat | RHSA-2023:6818 |
| Red Hat Satellite 6 | yggdrasil-worker-forwarder | 0.0.3-1.el8sat | RHSA-2023:6818 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| RubyGems | kubeclient | < 4.9.3 | 4.9.3 | GHSA-69p3-xp37-f692 |
Advisories 3
- RHSA-2023:6818 Red Hat Security Advisory: Satellite 6.14 security and bug fix update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- WID-SEC-2025-0001 IBM DB2: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 11, 2026
- WID-SEC-2022-0069 Red Hat OpenShift Logging Subsystem: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 3, 2025