cbcvebase.
CVE-2026-58253
published 2026-07-08

CVE-2026-58253: 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…

PriorityP355high8.8CVSS 3.1
AVAACLPRNUINSCCLIHAL
EPSS
0.37%
29.7th percentile
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.

Affected

4 ranges
VendorProductVersion rangeFixed in
linuxfoundationnats-server< 2.11.162.11.16
linuxfoundationnats-server>= 2.12.0 < 2.12.72.12.7
nats-ionats-server< 2.11.162.11.16
nats-ionats-server

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L
vendor_redhat8.8HIGH
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