CVE-2026-58253CWE-287

NATS Server: Route API Auth Bypass

High · published July 8, 2026

CVSS v3.1
8.8
EPSS
0%
Percentile
29.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L
CVSS v4.0
Not supplied
EPSS
0.00368 · 29.5th percentile
Weakness
CWE-287 · Improper Authentication
Published
2026-07-08T19:43Z
EPSS history
Timeline
  • 08 JUL 19:43Z
    NATS Server: Route API Auth Bypass
    cvelistv5