CVE-2026-49258
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk21th percentile - higher than 21% of all known CVEs
Summary
Nebula Mesh versions 0.3.5 and below do not apply per-operator CA scoping in the web UI, allowing any authenticated non-admin operator to access resources belonging to other operators. This was partially fixed in GHSA-598g-h2vc-h5vg but the web UI was not covered.
Risk Assessment
A malicious operator can block or delete other operators' hosts and read their networks, leading to confidentiality and integrity breaches.
Recommendation
Immediately upgrade Nebula Mesh to version 0.3.6, which includes the complete fix for the web UI.
Other vulnerabilities in Nebula Mesh
See all- CVE-2026-47724Critical
Vulnerability in nebula-mesh allows privilege escalation due to missing access controls on many API endpoints. Any operator with an API key can access resources of other operators.
- CVE-2026-48058Medium
nebula-mesh before version 0.3.2 sets HttpOnly and SameSite=Lax flags on cookies but never sets the Secure flag. A single plaintext request to the origin (e.g., operator on a LAN, mistyped URL, HTTP→HTTPS not strictly enforced, reverse proxy misconfiguration) discloses the session.
- CVE-2026-47768Medium
In nebula-mesh prior to version 0.3.2, a newly minted operator API key was exposed in the redirect URL, potentially leaking via Referer header, browser history, or proxy logs. This issue has been fixed in version 0.3.2.
- CVE-2026-47726High
nebula-mesh versions prior to 0.3.2 do not perform admin checks on the audit log endpoint. Any operator with an API key can read the full audit log, including cross-tenant data.
- CVE-2026-47725Medium
In nebula-mesh prior to version 0.3.3, all /ui/* POST/PUT/PATCH/DELETE routes process requests immediately after session cookie validation. SameSite=Lax does not protect against cross-site form submissions from third-party domains (e.g., top-level navigations, sibling-subdomain attacks) or against the GET /ui/logout route. This issue has been fixed in version 0.3.3.
- CVE-2026-48025Medium
In nebula-mesh prior to version 0.3.7, decrypted CA private keys remain in the process heap after use because they are not zeroed before memory release. This violates the keystore package contract and could lead to key leakage. This issue has been fixed in version 0.3.7.
- CVE-2026-47723High
In nebula-mesh before version 0.3.1, standard browser security headers (Content-Security-Policy, X-Frame-Options, Strict-Transport-Security, X-Content-Type-Options, Referrer-Policy) are missing in the internal/web/ and internal/api/ response paths. Fixed in version 0.3.1.
- CVE-2026-47722High
In nebula-mesh before version 0.3.2, in internal/configgen/generator.go, the ListenHost and TunDevice fields are interpolated without validation into a text/template, potentially leading to code injection. internal/web/advanced.go accepts these fields with only whitespace trimming, no character or shape validation.
Original NVD description (English source)
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.