How severe is CVE-2025-23047?

CVE-2025-23047 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2025-23047?

CVE-2025-23047 affects the following packages: github.com/cilium/cilium (Go), github.com/cilium/cilium (Go), github.com/cilium/cilium (Go). Ecosystems affected: Go.

How do I fix CVE-2025-23047?

Update github.com/cilium/cilium to 1.14.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-23047 is resolved across your whole dependency graph.

How do I detect CVE-2025-23047 in my Go dependencies?

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.

How do I mitigate CVE-2025-23047 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2025-23047?

O3 pinpoints whether CVE-2025-23047 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2025-23047 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-23047 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-23047?

CVE-2025-23047 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 38th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-23047?

CVE-2025-23047 is classified as Information Exposure (CWE-200). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-23047 published, and has it been updated?

CVE-2025-23047 was published on January 22, 2025 and was last updated on April 2, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

CVE-2025-23047

MEDIUM

Cilium vulnerable to information leakage via insecure default Hubble UI CORS header

Also known asBIT-cilium-2025-23047BIT-cilium-operator-2025-23047BIT-hubble-relay-2025-23047GHSA-h78m-j95m-5356GO-2025-3416

Published

Jan 22, 2025

Updated

Apr 2, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk38th percentile+0.43%

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

3 pkgs affected

🐹github.com/cilium/cilium🐹github.com/cilium/cilium🐹github.com/cilium/cilium

Real-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. An insecure default Access-Control-Allow-Origin header value could lead to sensitive data exposure for users of Cilium versions 1.14.0 through 1.14.7, 1.15.0 through 1.15.11, and 1.16.0 through 1.16.4 who deploy Hubble UI using either Cilium CLI or via the Cilium Helm chart. 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. This issue is fixed in Cilium v1.14.18, v1.15.12, and v1.16.5. As a workaround, 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 from commit a3489f190ba6e87b5336ee685fb6c80b1270d06d.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/cilium/cilium`	≥ 1.14.0&&< 1.14.19	1.14.19
🐹Go	`github.com/cilium/cilium`	≥ 1.15.0&&< 1.15.13	1.15.13
🐹Go	`github.com/cilium/cilium`	≥ 1.16.0&&< 1.16.6	1.16.6

Detection & mitigation playbook

Open-source dependency

Detect
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 1.14.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-23047 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-2025-23047 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-2025-23047. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Cilium is a networking, observability, and security solution with an eBPF-based dataplane. An insecure default `Access-Control-Allow-Origin` header value could lead to sensitive data exposure for users of Cilium versions 1.14.0 through 1.14.7, 1.15.0 through 1.15.11, and 1.16.0 through 1.16.4 who deploy Hubble UI using either Cilium CLI or via the Cilium Helm chart. 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 a

O3 Security · Impact-Aware SCA

Is CVE-2025-23047 in your dependencies?

O3 detects CVE-2025-23047 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works