CVE-2026-58213: linuxfoundation nats-server Injection

Vulnerability summary

CVE-2026-58213 is a high (CVSS 7.1) Injection vulnerability in linuxfoundation nats-server. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 36.9% of scored vulnerabilities.

Timeline

1. 08-07-2026
   PublishedVulnerability first disclosed.
2. 09-07-2026
   Last modifiedVulnerability information updated.

Description

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.1 and 2.12.9, an MQTT client could include protocol control characters in subscription filters that were later forwarded as NATS protocol data to route or leafnode connections, corrupting the forwarded protocol stream and allowing injection of unintended NATS protocol operations. This issue is fixed in versions 2.14.1 and 2.12.9.

• CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.