Cilium leaks information via incorrect ReferenceGrant update logic in Gateway API

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.4 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

EPSS

• CVE-2024-42486: 0.57% estimated exploitation activity in the next 30 days; percentile 47.41 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact Due to ReferenceGrant changes not being immediately propagated in Cilium's GatewayAPI controller, Gateway resources are able to access secrets in other namespaces after the associated ReferenceGrant has been revoked. This can lead to Gateways continuing to establish sessions using secrets that they should no longer have access to. Patches This issue was resolved in https://github.com/cilium/cilium/pull/34032. This issue affects: - Cilium v1.15 between v1.15.0 and v1.15.7 inclusive - Cilium v1.16.0 This issue has been patched in: - Cilium v1.15.8 - Cilium v1.16.1 Workarounds Any modification of a related Gateway/HTTPRoute/GRPCRoute/TCPRoute CRD (for example, adding any label to any of these resources) will trigger a reconciliation of ReferenceGrants on an affected cluster. Acknowledgements The Cilium community has worked together with members of Cure53 and Isovalent to prepare these mitigations. Special thanks to @sayboras for resolving this issue. For more information If you…

Published by the source

16 Aug 2024, 18:45 UTC

Last modified by the source

16 Aug 2024, 18:45 UTC

Source last checked

26 Oct 2026, 15:04 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-vwf8-q6fw-4wcm

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# Patch Next advisory brief: CVE-2024-42486

Advisory: Cilium leaks information via incorrect ReferenceGrant update logic in Gateway API
IDs: CVE-2024-42486, GHSA-vwf8-q6fw-4wcm
Record: https://patchnext.com/advisories/cve-2024-42486 (revision 1, source checked 26 Oct 2026, 15:04 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/cilium/cilium 1.16.1, 1.15.8. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/cilium/cilium: affected >= 1.16.0, <= 1.16.0; >= 1.15.0, < 1.15.8; fixed in 1.15.8, 1.16.1

## Suggested inspection (read-only)
- Go github.com/cilium/cilium: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/cilium/cilium.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-vwf8-q6fw-4wcm (GitHub-reviewed advisory GHSA-vwf8-q6fw-4wcm lists affected ranges: Go github.com/cilium/cilium >=1.16.0 =1.15.0 <1.15.8)

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