# CVE-2026-4604: Klubraum Membership Request <= 1.1.0 - Missing Authorization to Unauthenticated Arbitrary Plugin Settings Update

> Unauthenticated attackers can modify plugin settings and hijack API integrations due to missing capability checks in the Klubraum Membership Request plugin.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Jul 2026
- **Updated:** 29 Jul 2026
- **Also known as:** GHSA-fwgq-wmqx-h49q

## What is CVE-2026-4604?

CVE-2026-4604 is a medium-severity missing authorization vulnerability in Klubraum Membership Request, published on 29 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Klubraum Membership Request plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `kr_mr_store_settings()` function in all versions up to, and including, 1.1.0. This makes it possible for unauthenticated attackers to update the plugin's settings, including the Klubraum API token and introduction text, effectively hijacking the plugin's integration with the Klubraum service.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-4604?


## How do I fix CVE-2026-4604?

No fix has been published for CVE-2026-4604 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-4604 being exploited?

There is no known exploitation of CVE-2026-4604 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4604 and fix it if it is affected.

What it is: CVE-2026-4604 is a medium-severity missing authorization vulnerability in Klubraum Membership Request, published on 29 Jul 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-2026-4604 in the wild and no public exploit code.

Affected product: Klubraum Membership Request. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-4604/ (Markdown: https://insights.sbomify.com/CVE-2026-4604/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4604
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4604
- OSV: https://osv.dev/vulnerability/CVE-2026-4604

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-4604/
Summaries are generated and may contain mistakes; the official description above is the record.