CVE-2026-58250
Published:July 08, 2026
Updated:August 04, 2026
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
Affected Packages
https://github.com/nats-io/nats-server.git (GITHUB):
Affected version(s) >=v0.5.1 <v2.11.17Fix Suggestion:
Update to version v2.11.17https://github.com/nats-io/nats-server.git (GITHUB):
Affected version(s) >=v2.12.0 <v2.12.8Fix Suggestion:
Update to version v2.12.8github.com/nats-io/nats-server (GO):
Affected version(s) >=v0.0.0-20130930172406-45a99cc7e1a6 <v2.11.17Fix Suggestion:
Update to version v2.11.17github.com/nats-io/nats-server (GO):
Affected version(s) >=v2.12.0 <v2.12.8Fix Suggestion:
Update to version v2.12.8github.com/nats-io/nats-server/v2 (GO):
Affected version(s) >=v2.0.0-RC14.0.20190604014547-ed1901c79292 <v2.11.17Fix Suggestion:
Update to version v2.11.17github.com/nats-io/nats-server/v2 (GO):
Affected version(s) >=v2.12.0 <v2.12.8Fix Suggestion:
Update to version v2.12.8Related Resources (7)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
NULL Pointer Dereference
EPSS
Base Score:
0.51