7.5

CVE-2026-33219

NATS is vulnerable to pre-auth DoS through WebSockets client service

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Linuxfoundation ≫ Nats-server Version < 2.11.15
Linuxfoundation ≫ Nats-server Version >= 2.12.0 < 2.12.6
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.53% 0.409
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 5.3 3.9 1.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
0b0ca135-0b70-47e7-9f44-1890c2a1c46c 7.5 3.9 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-770 Allocation of Resources Without Limits or Throttling

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j
Vendor Advisory
Mitigation
https://advisories.nats.io/CVE/secnote-2026-02.txt
Vendor Advisory
Mitigation
https://advisories.nats.io/CVE/secnote-2026-11.txt
Vendor Advisory
Mitigation
https://github.com/advisories/GHSA-qrvq-68c2-7grw
Vendor Advisory
Mitigation
https://access.redhat.com/errata/RHSA-2026:21769
https://access.redhat.com/errata/RHSA-2026:22347
https://access.redhat.com/errata/RHSA-2026:23345
https://access.redhat.com/security/cve/CVE-2026-33219
https://bugzilla.redhat.com/show_bug.cgi?id=2451445
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33219.json