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 malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-server before authentication; this requires sending a corresponding amount of data. This is a milder variant of CVE-2026-27571. That earlier issue was a compression bomb, this vulnerability is not. Attacks against this new issue thus require significant client bandwidth. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable websockets if not required for project deployment.

INFO

Published Date :

2026-03-25T19:55:28.363Z

Last Modified :

2026-03-25T20:10:35.721Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-33219 vulnerability.

Vendors Products
Linuxfoundation
  • Nats-server
Nats
  • Nats Server
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-33219.

URL Resource
https://advisories.nats.io/CVE/secnote-2026-02.txt cve-icon cve-icon cve-icon
https://advisories.nats.io/CVE/secnote-2026-11.txt cve-icon cve-icon cve-icon
https://github.com/advisories/GHSA-qrvq-68c2-7grw cve-icon cve-icon cve-icon
https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-33219 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-33219 cve-icon
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CVSS Vulnerability Scoring System

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