Nebula Mesh: Web UI lacks ownership checks, enabling cross-operator access to hosts and networks (read, block, delete)

{
  "id": "b0eb7c13daee2a239626bc304d113b0e4867ad0d35010e7e89d998f34e41ffcf",
  "url": "https://osv.dev/vulnerability/CVE-2026-49258",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Nebula Mesh: Web UI lacks ownership checks, enabling cross-operator access to hosts and networks (read, block, delete)",
    "summary": "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.",
    "evidence": "osv:CVE-2026-49258",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-49258",
      "aliases": [
        "CVE-2026-49258",
        "GHSA-c6v2-3ffm-vcmc",
        "GO-2026-5816"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/forgekeep/nebula-mesh",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "01fdc54a2bc2e885048636576cab998c6f2c7fe9"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "0.3.6"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v0.3.5",
            "v0.3.4",
            "v0.3.3",
            "v0.3.2",
            "v0.3.1",
            "v0.3.0",
            "v0.2.0",
            "v0.1.2",
            "v0.1.1",
            "v0.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49258.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:27.654355099Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49258.json",
        "https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-c6v2-3ffm-vcmc",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-49258",
        "https://github.com/forgekeep/nebula-mesh/pull/161"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-639",
          "CWE-862"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49258.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-49258",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 494423,
  "published_at": "2026-07-28T18:52:58.713+00:00"
}