Traefik has Knative Ingress Rule Injection that Allows Host Restriction Bypass

Exploitation

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

CVSS 4.0

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

EPSS

• CVE-2026-32695: 0.47% estimated exploitation activity in the next 30 days; percentile 40.82 (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 potential vulnerability in Traefik's Kubernetes Knative, Ingress, and Ingress-NGINX providers related to rule injection. User-controlled values are interpolated into backtick-delimited Traefik router rule expressions without escaping or validation. A malicious value containing a backtick can terminate the literal and inject additional operators into Traefik's rule language, altering the parsed rule tree. In shared or multi-tenant deployments, this can bypass host and header routing constraints and redirect unauthorized traffic to victim services. Patches - https://github.com/traefik/traefik/releases/tag/v3.6.11 - https://github.com/traefik/traefik/releases/tag/v3.7.0-ea.2 For more information If there are any questions or comments about this advisory, please open an issue. <details <summaryOriginal Description</summary Summary Traefik's Knative provider builds router rules by interpolating user-controlled values into backtick-delimited rule expressions without…

Published by the source

27 Mar 2026, 17:49 UTC

Last modified by the source

27 Mar 2026, 17:49 UTC

Source last checked

26 Oct 2026, 15:18 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-67jx-r9pv-98rj

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# Patch Next advisory brief: CVE-2026-32695

Advisory: Traefik has Knative Ingress Rule Injection that Allows Host Restriction Bypass
IDs: CVE-2026-32695, GHSA-67jx-r9pv-98rj
Record: https://patchnext.com/advisories/cve-2026-32695 (revision 1, source checked 26 Oct 2026, 15:18 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: github.com/traefik/traefik/v3 3.7.0-ea.2, 3.6.11. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/traefik/traefik/v3: affected < 3.6.11; >= 3.7.0-ea.1, < 3.7.0-ea.2; fixed in 3.7.0-ea.2, 3.6.11
- Go github.com/traefik/traefik/v2: affected <= 2.11.42

## Suggested inspection (read-only)
- Go github.com/traefik/traefik/v3: check the installed version with your package manager.
- Go github.com/traefik/traefik/v2: 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/traefik/traefik/v3, github.com/traefik/traefik/v2.
- 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-67jx-r9pv-98rj (GitHub-reviewed advisory GHSA-67jx-r9pv-98rj lists affected ranges: Go github.com/traefik/traefik/v3 >=0 =3.7.0-ea.1 =0 <=2.11.42)

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