# CVE-2026-67309: Traefik v3.7.0 Path Traversal via RewriteTarget Authentication Bypass

> Attackers can bypass authentication on protected endpoints by exploiting path traversal in Traefik's Kubernetes Ingress NGINX provider rewrite rules.

- **Severity:** High 7.8 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 Aug 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-8rxv-jg7p-wvg3, GO-2026-6207, MINI-3r4h-h443-cwh9, MINI-4jhf-4cgr-g787, MINI-chxf-hh25-j4q5

## What is CVE-2026-67309?

CVE-2026-67309 is a high-severity path traversal vulnerability in Traefik Traefik, published on 1 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Traefik versions >= v3.7.0 and <= v3.7.7 contain a path traversal vulnerability in the Kubernetes Ingress NGINX provider's RewriteTarget middleware (generated from the nginx.ingress.kubernetes.io/rewrite-target annotation). When an Ingress path uses a regex that captures attacker-controlled text without requiring a path separator (e.g., path /api(.*) with rewrite target /$1), a crafted request such as /api../admin matches the public router, is rewritten to a dot-segment traversal path (/../admin), and is forwarded without post-replacement normalization validation. A backend that normalizes dot segments resolves the path to a protected endpoint (e.g., /admin) reachable only through a separate router secured with BasicAuth, DigestAuth, or ForwardAuth, resulting in route-level authentication bypass. The issue is fixed in v3.7.8.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-67309?

5 open source packages ship an affected version, including github.com/traefik/traefik/v3, github.com/traefik/traefik and github.com/traefik/traefik/v2. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/traefik/traefik/v3` | Go | From 3.7.0 | 3.7.8 |
| `github.com/traefik/traefik/v3` | Go | From 3.7.0 | 3.7.8 |
| `github.com/traefik/traefik/v3` | Go | From 3.7.0 | 3.7.8 |
| `github.com/traefik/traefik` | Go | All versions | None |
| `github.com/traefik/traefik/v2` | Go | All versions | None |

Products: Traefik Traefik.

## How do I fix CVE-2026-67309?

Upgrade github.com/traefik/traefik/v3 to 3.7.8 or later.

## Is CVE-2026-67309 being exploited?

There is no known exploitation of CVE-2026-67309 in the wild and no public exploit code.

## Other vulnerabilities in Traefik Traefik

- [CVE-2024-45410](https://insights.sbomify.com/CVE-2024-45410/): HTTP client can remove the X-Forwarded headers in Traefik (critical 9.8)
- [CVE-2026-88877](https://insights.sbomify.com/CVE-2026-88877/): Traefik v3.7.0 Authentication Bypass via from-to-www-redirect (critical 9.3)
- [CVE-2026-85595](https://insights.sbomify.com/CVE-2026-85595/): Traefik before v2.11.55 and v3.0.0 through v3.7.10 Authentication Bypass via digestAuth (critical 9.3)
- [CVE-2026-88007](https://insights.sbomify.com/CVE-2026-88007/): Traefik HTTP/3 Backend NTLM Connection Reuse (critical 9.1)
- [CVE-2026-88009](https://insights.sbomify.com/CVE-2026-88009/): Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-67309 and fix it if it is affected.

What it is: CVE-2026-67309 is a high-severity path traversal vulnerability in Traefik Traefik, published on 1 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-67309 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/traefik/traefik/v3 (Go): affected from 3.7.0; fixed in 3.7.8
- github.com/traefik/traefik/v3 (Go): affected from 3.7.0; fixed in 3.7.8
- github.com/traefik/traefik/v3 (Go): affected from 3.7.0; fixed in 3.7.8
- github.com/traefik/traefik (Go): affected all versions; no fix listed
- github.com/traefik/traefik/v2 (Go): affected all versions; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-67309/ (Markdown: https://insights.sbomify.com/CVE-2026-67309/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-67309
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-67309
- OSV: https://osv.dev/vulnerability/CVE-2026-67309

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-67309/
Summaries are generated and may contain mistakes; the official description above is the record.