CVE-2026-49258: Juev Nebula-Mesh

High severity, CVSS 8.8. EPSS: 0.5% chance of exploitation in the next 30 days.

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 products

• Juev Nebula-Mesh: before 0.3.6 (fixed in 0.3.6)

Published 2026-07-28. Last modified 2026-07-30.