Description
NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a client which can connect to the leafnode port can crash the nats-server with a certain malformed message pre-authentication. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable leafnode support if not needed or restrict network connections to the leafnode port, if plausible without compromising the service offered.
Scores
CVSS v3
7.5
EPSS
0.0024
EPSS Percentile
46.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-20
Status
published
Products (5)
linuxfoundation/nats-server
< 2.11.15
nats-io/nats-server
0Go
nats-io/nats-server
0 - 2.11.15Go
nats-io/nats-server
< < 2.11.15
nats-io/nats-server
>= 2.12.0-RC.1, < 2.12.6
Published
Mar 25, 2026
Tracked Since
Mar 26, 2026