CVE-2026-27889

Published: Mar 25, 2026 Last Modified: Mar 25, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,5
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high

Description

AI Translation Available

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.

190

Integer Overflow or Wraparound

Stable
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Availability Integrity Confidentiality Access Control Other
Potential Impacts:
Dos: Crash, Exit, Or Restart Dos: Resource Consumption (Memory) Dos: Instability Modify Memory Execute Unauthorized Code Or Commands Bypass Protection Mechanism Alter Execution Logic Dos: Resource Consumption (Cpu)
Applicable Platforms
Languages: C, Not Language-Specific
Likelihood of Exploit: Medium
View CWE Details
https://advisories.nats.io/CVE/secnote-2026-03.txt
https://advisories.nats.io/CVE/secnote-2026-03.txt
https://github.com/nats-io/nats-server/security/advisories/…
https://github.com/nats-io/nats-server/security/advisories/GHSA-pq2q-rcw4-3hr6