# CVE-2026-118658: Echo: Arbitrary Scheme Injection in WWWRedirect/NonWWWRedirect Middlewares via X-Forwarded-Proto


- **Severity:** Medium 4.7 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-118658, GHSA-23wf-92cp-8pcj, UBUNTU-CVE-2026-118658

## What is CVE-2026-118658?

CVE-2026-118658 is a medium-severity vulnerability in labstack echo, published on 28 Oct 2026. 

### Official description

Echo is a Go web framework. Prior to 4.15.2 and 5.1.1, Context.Scheme returns values from X-Forwarded-Proto, X-Forwarded-Protocol, or X-Url-Scheme without validating that they are supported web schemes. WWWRedirect and NonWWWRedirect use that value to construct a Location header, so an attacker controlling a forwarded scheme header can cause a redirect to use an arbitrary URI scheme. Exploitation requires an affected redirect middleware and user interaction with the response; the HTTPS-specific redirect variants hardcode HTTPS and are unaffected. This issue is fixed in 4.15.2 and 5.1.1.

Weakness: CWE-601 (URL Redirection to Untrusted Site)

## Which versions are affected by CVE-2026-118658?

4 open source packages ship an affected version, including github.com/labstack/echo/v4 and github.com/labstack/echo/v5.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/labstack/echo/v4` | Go | All versions | 4.15.2 |
| `github.com/labstack/echo/v4` | Go | All versions | 4.15.2 |
| `github.com/labstack/echo/v5` | Go | All versions | 5.1.1 |
| `github.com/labstack/echo/v5` | Go | All versions | 5.1.1 |

## How do I fix CVE-2026-118658?

Upgrade github.com/labstack/echo/v4 to 4.15.2 or later.

## Is CVE-2026-118658 being exploited?

There is no known exploitation of CVE-2026-118658 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-118658 and fix it if it is affected.

What it is: CVE-2026-118658 is a medium-severity vulnerability in labstack echo, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-118658 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/labstack/echo/v4 (Go): affected all versions; fixed in 4.15.2
- github.com/labstack/echo/v4 (Go): affected all versions; fixed in 4.15.2
- github.com/labstack/echo/v5 (Go): affected all versions; fixed in 5.1.1
- github.com/labstack/echo/v5 (Go): affected all versions; fixed in 5.1.1

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-2026-118658/ (Markdown: https://insights.sbomify.com/CVE-2026-118658/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-118658
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-118658
- OSV: https://osv.dev/vulnerability/CVE-2026-118658

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-118658/
Summaries are generated and may contain mistakes; the official description above is the record.