CVE-2023-34242
LOWCVE-2023-34242 is a low-severity (CVSS 3.4) Information Exposure vulnerability in github.com/cilium/cilium. O3 Security confirms whether CVE-2023-34242 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cilium vulnerable to information leakage via incorrect ReferenceGrant handling
Blast Radius
github.com/cilium/ciliumReal-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
Cilium is a networking, observability, and security solution with an eBPF-based dataplane. Prior to version 1.13.4, when Gateway API is enabled in Cilium, the absence of a check on the namespace in which a ReferenceGrant is created could result in Cilium unintentionally gaining visibility of secrets (including certificates) and services across namespaces. An attacker on an affected cluster can leverage this issue to use cluster secrets that should not be visible to them, or communicate with services that they should not have access to. Gateway API functionality is disabled by default. This vulnerability is fixed in Cilium release 1.13.4. As a workaround, restrict the creation of ReferenceGrant resources to admin users by using Kubernetes RBAC.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cilium/cilium | ≥ 1.13.0&&< 1.13.4 | 1.13.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cilium/cilium. 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 github.com/cilium/cilium to 1.13.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-34242 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-2023-34242 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-2023-34242. 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-2023-34242 in your dependencies?
O3 detects CVE-2023-34242 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.