# CVE-2026-29054: Traefik: lowercase `Connection` tokens can delete traefik-managed forwarded identity headers (for example, `X-Real-Ip`)

> Remote attackers can bypass header protection mechanisms to delete Traefik-managed forwarded identity headers, potentially spoofing client IP addresses.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 5 Mar 2026
- **Updated:** 15 Jul 2026
- **Also known as:** CLEANSTART-2026-HF02627, GHSA-92mv-8f8w-wq52, GO-2026-4597, MINI-4345-5956-748p, MINI-5h9q-fmqj-99q7

## What is CVE-2026-29054?

CVE-2026-29054 is a high-severity vulnerability in Traefik Traefik, published on 5 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Traefik is an HTTP reverse proxy and load balancer. From version 2.11.9 to 2.11.37 and from version 3.1.3 to 3.6.8, there is a potential vulnerability in Traefik managing the Connection header with X-Forwarded headers. When Traefik processes HTTP/1.1 requests, the protection put in place to prevent the removal of Traefik-managed X-Forwarded headers (such as X-Real-Ip, X-Forwarded-Host, X-Forwarded-Port, etc.) via the Connection header does not handle case sensitivity correctly. The Connection tokens are compared case-sensitively against the protected header names, but the actual header deletion operates case-insensitively. As a result, a remote unauthenticated client can use lowercase Connection tokens (e.g. Connection: x-real-ip) to bypass the protection and trigger the removal of Traefik-managed forwarded identity headers. This issue has been patched in versions 2.11.38 and 3.6.9.

Weakness: CWE-178 (Improper Handling of Case Sensitivity)

## Which versions are affected by CVE-2026-29054?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/traefik/traefik/v2` | Go | From 2.11.9 | 2.11.38 |
| `github.com/traefik/traefik/v2` | Go | From 2.11.9 | 2.11.38 |
| `github.com/traefik/traefik/v2` | Go | From 2.11.9 | 2.11.38 |
| `github.com/traefik/traefik` | Go | All versions | None |
| `github.com/traefik/traefik/v3` | Go | From 3.1.3 | 3.6.9 |
| `github.com/traefik/traefik/v3` | Go | From 3.1.3 | 3.6.9 |
| `github.com/traefik/traefik/v3` | Go | From 3.1.3 | 3.6.9 |

Products: Traefik Traefik.

## How do I fix CVE-2026-29054?

Upgrade github.com/traefik/traefik/v2 to 2.11.38 or later.

## Is CVE-2026-29054 being exploited?

There is no known exploitation of CVE-2026-29054 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-2026-29054 and fix it if it is affected.

What it is: CVE-2026-29054 is a high-severity vulnerability in Traefik Traefik, published on 5 Mar 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-2026-29054 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/traefik/traefik/v2 (Go): affected from 2.11.9; fixed in 2.11.38
- github.com/traefik/traefik/v2 (Go): affected from 2.11.9; fixed in 2.11.38
- github.com/traefik/traefik/v2 (Go): affected from 2.11.9; fixed in 2.11.38
- github.com/traefik/traefik (Go): affected all versions; no fix listed
- github.com/traefik/traefik/v3 (Go): affected from 3.1.3; fixed in 3.6.9
- github.com/traefik/traefik/v3 (Go): affected from 3.1.3; fixed in 3.6.9
- github.com/traefik/traefik/v3 (Go): affected from 3.1.3; fixed in 3.6.9

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-2026-29054/ (Markdown: https://insights.sbomify.com/CVE-2026-29054/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-29054
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-29054
- OSV: https://osv.dev/vulnerability/CVE-2026-29054

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-29054/
Summaries are generated and may contain mistakes; the official description above is the record.