CVE-2025-64432
MEDIUMKubeVirt Affected by an Authentication Bypass in Kubernetes Aggregation Layer
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.
Blast Radius
kubevirt.io/kubevirt🐹kubevirt.io/kubevirt🐹kubevirt.io/kubevirtReal-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
KubeVirt is a virtual machine management add-on for Kubernetes. Versions 1.5.3 and below, and 1.6.0 contained a flawed implementation of the Kubernetes aggregation layer's authentication flow which could enable bypass of RBAC controls. It was discovered that the virt-api component fails to correctly authenticate the client when receiving API requests over mTLS. In particular, it fails to validate the CN (Common Name) field in the received client TLS certificates against the set of allowed values defined in the extension-apiserver-authentication configmap. Failre to validate certain fields in the client TLS certificate may allow an attacker to bypass existing RBAC controls by directly communicating with the aggregated API server, impersonating the Kubernetes API server and its aggregator component. This issue is fixed in versions 1.5.3 and 1.6.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | kubevirt.io/kubevirt | all versions | 1.5.3 |
| 🐹Go | kubevirt.io/kubevirt | ≥ 1.6.0-alpha.0&&< 1.6.1 | 1.6.1 |
| 🐹Go | kubevirt.io/kubevirt | ≥ 1.7.0-alpha.0&&< 1.7.0-rc.0 | 1.7.0-rc.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for kubevirt.io/kubevirt. 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 kubevirt.io/kubevirt to 1.5.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-64432 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 CVE-2025-64432 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 CVE-2025-64432. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-64432 in your dependencies?
O3 detects CVE-2025-64432 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.