CVE-2026-47722: Forgekeep nebula-mesh YAML injection in agent config generator

CVE-2026-47722 · Severity: high · CVSS 4 · Published 2026-07-23

Nebula-mesh is a management tool for Slack Nebula virtual private networks. A security flaw allowed users with basic access to inject malicious configuration settings into the system. This could allow an attacker to take control of network traffic, promote their own devices to central network hubs (lighthouses), or intercept data from other users on the mesh network.

Technologies: Forgekeep Nebula-Mesh, github.com/juev/nebula-mesh (Go). Vendors: Forgekeep, Go.

Quick answers

Is CVE-2026-47722 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-47722 being exploited in the wild.
How severe is CVE-2026-47722?
High severity, with a CVSS score of 4, published 23 July 2026.
Which products and versions are affected?
Forgekeep Nebula-Mesh < 0.3.2; github.com/juev/nebula-mesh (Go) < 0.3.2, SEMVER:introduced=0,fixed=0.3.2.
Is there a fix for CVE-2026-47722?
Yes. github.com/juev/nebula-mesh (Go): upgrade to 0.3.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-47722 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-47722?
Check whether you run Forgekeep Nebula-Mesh or github.com/juev/nebula-mesh (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/juev/nebula-mesh (Go): upgrade to 0.3.2 or later
    go get github.com/juev/nebula-mesh@v0.3.2

Technical details

A YAML injection vulnerability exists in nebula-mesh prior to version 0.3.2. The `internal/configgen/generator.go` component used `text/template` to interpolate operator-supplied fields like `ListenHost` and `TunDevice` directly into the agent's `config.yml` without proper validation or escaping. An attacker with operator-level access can provide specially crafted strings containing newlines and YAML structural characters to inject arbitrary configuration keys. This allows for privilege escalation, such as self-promoting a node to a lighthouse or relay, potentially intercepting or redirecting mesh traffic. The issue was resolved by migrating from string-based templates to typed-struct marshalling using `yaml.v3`.

Affected products

  • forgekeep nebula-mesh < 0.3.2

Identifiers

  • CVE-2026-47722
  • GHSA-7hp6-g3pq-3pc3
  • GO-2026-5223

Timeline

  • 2026-05-20: disclosed: Initial advisory published on GitHub
  • 2026-05-21: patched: Fix committed to main branch
  • 2026-07-23: advisory: CVE published to NVD

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.