7.5

CVE-2026-27889

NATS: Pre-auth remote server crash via WebSocket frame length overflow in wsRead

NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Starting in version 2.2.0 and prior to versions 2.11.14 and 2.12.5, a missing sanity check on a WebSockets frame could trigger a server panic in the nats-server.  This happens before authentication, and so is exposed to anyone who can connect to the websockets port. Versions 2.11.14 and 2.12.5 contains a fix. A workaround is available. The vulnerability only affects deployments which use WebSockets and which expose the network port to untrusted end-points. If one is able to do so, a defense in depth of restricting either of these will mitigate the attack.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Linuxfoundation ≫ Nats-server Version >= 2.2.0 < 2.11.14
Linuxfoundation ≫ Nats-server Version >= 2.12.0 < 2.12.5
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.41% 0.328
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 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-190 Integer Overflow or Wraparound

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

https://github.com/nats-io/nats-server/security/advisories/GHSA-pq2q-rcw4-3hr6
Vendor Advisory
Mitigation
https://advisories.nats.io/CVE/secnote-2026-03.txt
Vendor Advisory
Mitigation