Traefik Kubernetes Ingress NGINX provider fails open when auth-secret resolution fails

Exploitation

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

CVSS 4.0

5.9 · CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N · score source

EPSS

• CVE-2026-54762: 0.43% estimated exploitation activity in the next 30 days; percentile 37.76 (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.

Summary There is a medium severity vulnerability in Traefik's Kubernetes Ingress NGINX provider that causes affected routes to fail open. When an Ingress explicitly enables BasicAuth or DigestAuth through the supported nginx.ingress.kubernetes.io/auth-type and auth-secret annotations, but the referenced auth Secret cannot be resolved or parsed, Traefik logs the resolution error, skips installing the authentication middleware, and still emits a router to the backend service. A route that operators intended to protect is therefore published to the data plane without its authentication control, allowing unauthenticated access to the backend. The trigger is an invalid or unresolved auth dependency — a missing, malformed, unreadable, or policy-denied Secret — rather than an intentionally unprotected route. Patches - https://github.com/traefik/traefik/releases/tag/v3.7.5 For more information If you have any questions or comments about this advisory, please open an issue. <details…

Published by the source

19 Jun 2026, 21:15 UTC

Last modified by the source

20 Jul 2026, 21:13 UTC

Source last checked

26 Oct 2026, 15:25 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-4mr2-fg2p-w63c

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# Patch Next advisory brief: CVE-2026-54762

Advisory: Traefik Kubernetes Ingress NGINX provider fails open when auth-secret resolution fails
IDs: CVE-2026-54762, GHSA-4mr2-fg2p-w63c
Record: https://patchnext.com/advisories/cve-2026-54762 (revision 1, source checked 26 Oct 2026, 15:25 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/traefik/traefik/v3 3.7.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/traefik/traefik/v3: affected >= 3.7.0-ea.1, <= 3.7.4; fixed in 3.7.5

## Suggested inspection (read-only)
- Go github.com/traefik/traefik/v3: 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/traefik/traefik/v3.
- 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-4mr2-fg2p-w63c (GitHub-reviewed advisory GHSA-4mr2-fg2p-w63c lists affected ranges: Go github.com/traefik/traefik/v3 >=3.7.0-ea.1 <=3.7.4)

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