5.3

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)
LinuxfoundationNats-server Version < 2.11.15
LinuxfoundationNats-server Version >= 2.12.0 < 2.12.6
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.11% 0.295
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
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 restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.