Authorization Flaw in github.com/traefik/traefik (CVE-2026-65602)
Summary
Vulnerability in github.com/traefik/traefik (CVE-2026-65602). Successful exploitation can lead to full system takeover. Exploitable via crossProviderNamespaces. Mitigation: upgrade to 3.7.7 or later.
Original description
The description as published by the source.
Summary
There is a medium-severity cross-provider reference vulnerability in Traefik's Kubernetes CRD provider. The crossProviderNamespaces allowlist is enforced for HTTP serversTransport references but was not enforced for IngressRouteTCP service serversTransport references. A low-privileged Kubernetes user in a namespace that is not listed in crossProviderNamespaces could set serversTransport: foo@file on an IngressRouteTCP service, causing Traefik to accept the forbidden cross-provider reference and use the file-provider TCPServersTransport — including privileged backend mTLS client certificates, SPIFFE identity, or PROXY-protocol settings. The fix applies the crossProviderNamespaces allowlist to TCP serversTransport references.
Patches
- https://github.com/traefik/traefik/releases/tag/v3.6.23
- https://github.com/traefik/traefik/releases/tag/v3.7.7
For more information
If you have any questions or comments about this advisory, please open an issue.
Original Description
Summary
Traefik's Kubernetes CRD provider enforces crossProviderNamespaces for several
cross-provider references, but IngressRouteTCP service
serversTransport references skip that allowlist. A low-privileged Kubernetes
user in a namespace that is not listed in crossProviderNamespaces can still
set serversTransport: foo@file on an IngressRouteTCP service. Traefik
accepts the forbidden cross-provider reference and…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-65602 has been found in github.com/traefik/traefik.
Attackers can target a specific entry point like crossProviderNamespaces over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: upgrade github.com/traefik/traefik to 3.7.7 or later.
If unsure, ask your IT team or search "github.com/traefik/traefik CVE-2026-65602" on the vendor's site.
CVE-2026-65602 (github.com/traefik/traefik) — CWE-863 / CVSS v3 8.8
Attack vector: remote (network-reachable) / no user interaction
Attack surface: crossProviderNamespaces / serversTransport / IngressRouteTCP / TCPServersTransport
Patched: 3.7.7 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Incorrect authorization (CWE-863) exists in github.com/traefik/traefik. Attackers reach the vulnerable code path via crossProviderNamespaces.
Check the vendor advisory for the affected versions of github.com/traefik/traefik. Attack surface: crossProviderNamespaces / serversTransport / IngressRouteTCP / TCPServersTransport.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to 3.7.7.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/traefik/traefik' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/traefik/traefik' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/traefik/traefikを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade github.com/traefik/traefik to 3.7.7ステージング環境で 3.7.7 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- patch disclosure@vulncheck.com
- web github.com
- web vulncheck.com
- web github.com
- web github.com
- web github.com
- web github.com
- web github.com
- web github.com