# CVE-2026-79746: MCPHub: Server-scoped bearer key gains access to an entire group via partial (any-overlap) server matching

> Attackers with a key scoped to one server can access all servers in the same group due to flawed authorization logic in MCPHub.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 31 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-454m-4vm6-842f

## What is CVE-2026-79746?

CVE-2026-79746 is a high-severity missing authorization vulnerability in samanhappy mcphub, published on 31 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

MCPHub is a unified hub for centrally managing and dynamically orchestrating multiple MCP servers/APIs into separate endpoints with flexible routing strategies. Prior to version 1.0.31, when a bearer key with accessType: 'servers' (or 'custom') is used against a group route, isBearerKeyAllowedForRequest grants access to the entire group as long as any single server in that group appears in the key's allowedServers list — not only when every server the key is scoped to matches, and critically, without ever re-checking allowedServers again once the group-level connection is authorized. A key explicitly scoped to one specific server therefore also grants full access to every other server that happens to share a group with it, including servers the key was never authorized for. This issue has been patched in version 1.0.31.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-79746?


## How do I fix CVE-2026-79746?

No fix has been published for CVE-2026-79746 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-79746 being exploited?

There is no known exploitation of CVE-2026-79746 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-79746 and fix it if it is affected.

What it is: CVE-2026-79746 is a high-severity missing authorization vulnerability in samanhappy mcphub, published on 31 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-79746 in the wild and no public exploit code.

Affected product: samanhappy mcphub. 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-2026-79746/ (Markdown: https://insights.sbomify.com/CVE-2026-79746/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-79746
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-79746
- OSV: https://osv.dev/vulnerability/CVE-2026-79746

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-79746/
Summaries are generated and may contain mistakes; the official description above is the record.