CVE-2026-58250: Linuxfoundation Nats-Server

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

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 products

• Linuxfoundation Nats-Server: before 2.11.17 (fixed in 2.11.17); from 2.12.0, before 2.12.8 (fixed in 2.12.8)

Published 2026-07-08. Last modified 2026-07-13.