Is CVE-2026-58207 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-58207 being exploited in the wild.

How severe is CVE-2026-58207?

High severity, with a CVSS score of 7.7, published 8 July 2026.

Which products and versions are affected?

nats-io nats-server = 2.14.0-RC.1, < 2.14.3.

Is there a fix for CVE-2026-58207?

A patch was published on 2026-06-29: Versions 2.14.3 and 2.12.12 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-58207 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-58207?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-58207: NATS Server integer overflow in Connz pagination monitoring requests

Q: Is there a fix for CVE-2026-58207?

A patch was published on 2026-06-29: Versions 2.14.3 and 2.12.12 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-58207 attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected by CVE-2026-58207?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-58207 · Severity: high · CVSS 7.7 · Published 2026-07-08

NATS Server is a high-performance messaging system used for cloud and edge computing. A vulnerability in how the server handles monitoring requests allows a connected user to crash the server by sending specially crafted messages. This results in a denial-of-service, disrupting communication across the entire messaging network.

Quick answers

Is CVE-2026-58207 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-58207 being exploited in the wild.
How severe is CVE-2026-58207?: High severity, with a CVSS score of 7.7, published 8 July 2026.
Which products and versions are affected?: nats-io nats-server < 2.12.12, >= 2.14.0-RC.1, < 2.14.3.
Is there a fix for CVE-2026-58207?: A patch was published on 2026-06-29: Versions 2.14.3 and 2.12.12 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-58207 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-58207?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An integer overflow vulnerability (CWE-190) exists in the NATS Server monitoring endpoints (Connz and Subsz). The flaw is located in the pagination logic where 'Offset' and 'Limit' values are processed; specifically, these values can overflow internal arithmetic before the response window is safely bounded. An attacker with the ability to send account-scoped connection monitoring requests can exploit this to trigger a panic and crash the server. In no-auth deployments, any client with network access can trigger the crash, while in multi-tenant environments, the attacker must have permissions to publish to the account monitoring request subject. The issue is resolved in versions 2.14.3 and 2.12.12.

Affected products

nats-io nats-server < 2.12.12, >= 2.14.0-RC.1, < 2.14.3

Timeline

2026-06-29: patched: Versions 2.14.3 and 2.12.12 released
2026-06-29: advisory: GitHub Security Advisory GHSA-q59r-vq66-pxc2 published
2026-07-08: disclosed: CVE-2026-58207 published to NVD

References

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