GHSA-h78m-j95m-5356 BIT-cilium-2025-23047 BIT-cilium-operator-2025-23047 BIT-hubble-relay-2025-23047 CVE-2025-23047 GO-2025-3416
Cilium has an information leakage via insecure default Hubble UI CORS header
- Severity
- 6.5 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.49%
- Chance of exploitation in the next 30 days. Higher than 42.08% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
- Fix
1.14.19- Upgrade github.com/cilium/cilium to this version or later
Description
Impact
For users who deploy Hubble UI using either Cilium CLI or via the Cilium Helm chart, an insecure default Access-Control-Allow-Origin header value could lead to sensitive data exposure. A user with access to a Hubble UI instance affected by this issue could leak configuration details about the Kubernetes cluster which Hubble UI is monitoring, including node names, IP addresses, and other metadata about workloads and the cluster networking configuration. In order for this vulnerability to be exploited, a victim would have to first visit a malicious page.
Patches
This issue was patched in https://github.com/cilium/cilium/commit/a3489f190ba6e87b5336ee685fb6c80b1270d06d
This issue affects:
- Cilium between v1.14.0 and v1.14.18 inclusive
- Cilium between v1.15.0 and v1.15.12 inclusive
- Cilium between v1.16.0 and v1.16.5 inclusive
This issue is patched in:
- Cilium v1.14.19
- Cilium v1.15.13
- Cilium v1.16.6
Workarounds
Users who deploy Hubble UI using the Cilium Helm chart directly can remove the CORS headers from the Helm template as shown in the patch.
Acknowledgements
The Cilium community has worked together with members of Isovalent to prepare these mitigations. Special thanks to @ciffelia for reporting this issue and to @geakstr for the fix.
For more information
If you have any questions or comments about this advisory, please reach out on Slack.
If you think you have found a vulnerability affecting Cilium, we strongly encourage you to report it to our security mailing list at security@cilium.io. This is a private mailing list for the Cilium security team, and your report will be treated as top priority.
Affected versions
Go
| Package | Vulnerable | Fixed in |
|---|---|---|
| github.com/cilium/cilium | >= 1.14.0, < 1.14.19 |
1.14.19 |
| github.com/cilium/cilium | >= 1.15.0, < 1.15.13 |
1.15.13 |
| github.com/cilium/cilium | >= 1.16.0, < 1.16.6 |
1.16.6 |
| github.com/cilium/cilium | >= 1.14.0, < 1.14.19>= 1.15.0, < 1.15.13>= 1.16.0, < 1.16.6 |
1.14.191.15.131.16.6 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
github.com/cilium/cilium Go → 1.14.19
- go
go get github.com/cilium/cilium@v1.14.19 && go mod tidy
Severity breakdown
CVSS 3.1 6.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Weakness
CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
How to prevent it
- Architecture and Design: Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-fm8w-2m5w-9j7r Cilium may unexpectedly allow ingress traffic from the local namespace when a Kubernetes NetworkPolicy is configured with an ipBlock match | Medium | Also affects github.com/cilium/cilium |
| GHSA-w7c2-w76w-5hmj Cilium: Namespaced HTTPRoutes can redirect traffic to other namespaces | High | Also affects github.com/cilium/cilium |
| GHSA-q6h5-q3q6-f87x CiliumLocalRedirectPolicy addressMatcher allows cross-namespace service traffic hijacking and can break service translation | Medium | Also affects github.com/cilium/cilium |
| GHSA-3fcv-jvfp-m4q9 Cilium vulnerable to sensitive information disclosure and cluster disruption via local Envoy admin socket access | High | Also affects github.com/cilium/cilium |
| GHSA-gj49-89wh-h4gj Cillium exposes sensitive information included in the cilium-bugtool debug archive | Medium | Also affects github.com/cilium/cilium |
| GHSA-hxv8-4j4r-cqgv Cilium L7 proxy may bypass Kubernetes NetworkPolicy for same-node traffic | Medium | Also affects github.com/cilium/cilium |
| GHSA-5r23-prx4-mqg3 Cilium may not enforce host firewall policies when Native Routing, WireGuard and Node Encryption are enabled | Medium | Also affects github.com/cilium/cilium |
| GHSA-38pp-6gcp-rqvm Cilium with misconfigured toGroups in policies can lead to unrestricted egress traffic | Medium | Also affects github.com/cilium/cilium |
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