Unauthenticated Admission Webhook Endpoints in Yoke ATC

Exploitation

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

CVSS

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

EPSS

• CVE-2026-26055: 0.47% estimated exploitation activity in the next 30 days; percentile 40.42 (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.

Unauthenticated Admission Webhook Endpoints in Yoke ATC This vulnerability exists in the Air Traffic Controller (ATC) component of Yoke, a Kubernetes deployment tool. The ATC webhook endpoints lack proper authentication mechanisms, allowing any pod within the cluster network to directly send AdmissionReview requests to the webhook, bypassing Kubernetes API Server authentication. This enables attackers to trigger WASM module execution in the ATC controller context without proper authorization. Recommended CWE: CWE-306 (Missing Authentication for Critical Function) Summary Yoke ATC implements multiple Admission Webhook endpoints (/validations/{airway}, /validations/resources, /validations/flights.yoke.cd, /validations/airways.yoke.cd, etc.) that process AdmissionReview requests. These endpoints do not implement TLS client certificate authentication or request source validation. Any client that can reach the ATC service within the cluster can send requests directly to these endpoints,…

Published by the source

12 Feb 2026, 22:06 UTC

Last modified by the source

13 Feb 2026, 17:15 UTC

Source last checked

26 Oct 2026, 15:14 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-965m-v4cc-6334

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# Patch Next advisory brief: CVE-2026-26055

Advisory: Unauthenticated Admission Webhook Endpoints in Yoke ATC
IDs: CVE-2026-26055, GHSA-965m-v4cc-6334
Record: https://patchnext.com/advisories/cve-2026-26055 (revision 1, source checked 26 Oct 2026, 15:14 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/yokecd/yoke: affected <= 0.19.0

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

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/yokecd/yoke.
- 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-965m-v4cc-6334 (GitHub-reviewed advisory GHSA-965m-v4cc-6334 lists affected ranges: Go github.com/yokecd/yoke >=0 <=0.19.0)

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