NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.0, 2.12.7, and 2.11.16, when no_auth_user was configured, a parser fast path intended for ordinary client connections could also apply to route or leafnode listeners, allowing an unauthenticated peer to bypass inter-server CONNECT authentication and operate with the privileges associated with that connection type. This issue is fixed in versions 2.14.0, 2.12.7, and 2.11.16.
{
"license": "CC-BY-4.0",
"sources": [
{
"url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-58253",
"html_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-58253",
"database_specific": {
"status": "Analyzed"
},
"id": "CVE-2026-58253",
"published": "2026-07-08T20:16:54.943Z",
"imported": "2026-08-03T18:16:27.685Z",
"modified": "2026-07-13T15:25:44.430Z"
}
]
}