Vulnerability · Published Jul 28, 2026 · Assigned by GitHub_M
CVE-2026-49258Nebula Mesh: Web UI lacks ownership checks, enabling cross-operator access to hosts and networks (read, block, delete)
High 8.8
In plain English
A high-severity authorization bypass via user-controlled key in nebula-mesh from juev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).
Official description
Nebula Mesh is a self-hosted control plane for the Slack Nebula mesh VPN. In versions 0.3.5 and below, the web UI (/ui/*) does not apply the per-operator CA scoping employed by the JSON API. This was partially addressed by GHSA-598g-h2vc-h5vg, but the changes were not implemented in the web read/mutation surface. Any authenticated non-admin operator (for example, one created via self-registration or OIDC) can access resources belonging to other operators. The host create/edit/mobile-bundle/network-create paths and all CA-management routes were already correctly scoped. A malicious operator could block or delete any other operator's host, or read any operator's hosts and networks. This issue has been fixed in version 0.3.6.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/juev/nebula-mesh | no fix listed | GHSA-c6v2-3ffm-vcmc |
| Go | github.com/juev/nebula-mesh | no fix listed | GO-2026-5816 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| juev | nebula-mesh | < 0.3.6 |
Weakness: CWE-639, CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-c6v2-3ffm-vcmc x_refsource_CONFIRM
- https://github.com/forgekeep/nebula-mesh/pull/161 x_refsource_MISC