CVE-2026-58250

NATS Server: Pre-auth server crash via double INFO in leafnode handshake

Published: Jul 8, 2026Updated: Jul 13, 2026 Sources: CVE List NVDCWE-476

7.5HIGH

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-476

Affected Products

linuxfoundation

oss-project·USaka yocto, pytorch, everest

nats-serverOn-premDatabase

AI / ML / vector-db-rag

nats-io

oss-project

nats-serverOn-prem

Databases / cache-message-queue

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Impact

Initial Access

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References

https://github.com/nats-io/nats-server/commit/8dcb26eaea78fdcbe96dbee5986d6019fd5cb94a

github.com

https://github.com/nats-io/nats-server/commit/fc5fe39177533e9dbdd651d2458285bfae1dde27

github.com

https://github.com/nats-io/nats-server/releases/tag/v2.11.17

github.com

and 2 more references View all →

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