# CVE-2026-63464: Nebula-mesh allows non-admin operators to disable webhook SSRF protection via `allow_private`

> Non-admin operators can bypass SSRF protections to force the server to request internal network addresses.

- **Severity:** High 7.7 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/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:** Yes
- **Published:** 4 Sep 2026
- **Updated:** 8 Sep 2026
- **Also known as:** GHSA-7rx3-5wx3-5v76, GO-2026-5985

## What is CVE-2026-63464?

CVE-2026-63464 is a high-severity server-side request forgery vulnerability in forgekeep nebula-mesh, published on 4 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. From version 0.6.0 to before version 0.7.2, non-admin operators (role user) can set allow_private: true on their own managed webhook subscription (POST/PATCH /api/v1/webhook-subscriptions). No admin check exists on this field. At delivery time, allow_private switches the dispatcher to an unguarded HTTP client, bypassing the private/loopback/link-local SSRF guard — letting a low-privilege operator make the server request internal addresses. This issue has been patched in version 0.7.2.

Weakness: CWE-918 (Server-Side Request Forgery), CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-63464?

3 open source packages ship an affected version, including github.com/forgekeep/nebula-mesh.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/forgekeep/nebula-mesh` | Go | From 0.6.0 | 0.7.2 |
| `github.com/forgekeep/nebula-mesh` | Go | From 0.6.0 | 0.7.2 |
| `github.com/forgekeep/nebula-mesh` | Go | From 0.6.0 | 0.7.2 |

## How do I fix CVE-2026-63464?

Upgrade github.com/forgekeep/nebula-mesh to 0.7.2 or later.

## Is CVE-2026-63464 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63464 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63464 and fix it if it is affected.

What it is: CVE-2026-63464 is a high-severity server-side request forgery vulnerability in forgekeep nebula-mesh, published on 4 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63464 exists.

Affected packages and fixed versions:
- github.com/forgekeep/nebula-mesh (Go): affected from 0.6.0; fixed in 0.7.2
- github.com/forgekeep/nebula-mesh (Go): affected from 0.6.0; fixed in 0.7.2
- github.com/forgekeep/nebula-mesh (Go): affected from 0.6.0; fixed in 0.7.2

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-2026-63464/ (Markdown: https://insights.sbomify.com/CVE-2026-63464/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63464
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63464
- OSV: https://osv.dev/vulnerability/CVE-2026-63464

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-63464/
Summaries are generated and may contain mistakes; the official description above is the record.