CVE-2026-27889
7.5 · HIGHOverview
CVE-2026-27889 is a high-severity vulnerability affecting linuxfoundation nats-server. It was published on March 25, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from linuxfoundation. Update nats-server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| linuxfoundation | nats-server | >= 2.2.0, < 2.11.14 | Affected |
References
Frequently Asked Questions
What is CVE-2026-27889?
CVE-2026-27889 is a high-severity vulnerability affecting linuxfoundation nats-server. It was published on March 25, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-27889?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-27889?
Check the references section for vendor advisories and patches from linuxfoundation. Update nats-server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-27889?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-27889 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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