Is CVE-2026-40304 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-40304 being exploited in the wild.

How severe is CVE-2026-40304?

Medium severity, with a CVSS score of 5.3, published 17 April 2026.

Which products and versions are affected?

github.com/openziti/zrok (Go) <= 1.1.11, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.1.11; github.com/openziti/zrok/v2 (Go) < 2.0.1, SEMVER:introduced=0,fixed=2.0.1.

Is there a fix for CVE-2026-40304?

Yes. github.com/openziti/zrok/v2 (Go): upgrade to 2.0.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Am I affected by CVE-2026-40304?

Check whether you run github.com/openziti/zrok (Go), github.com/openziti/zrok/v2 (Go) or Netfoundry Zrok at an affected version. 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-2026-40304: zrok: Broken ownership check in DELETE /api/v2/unaccess allows non-admin to delete global frontend records

Q: Is there a fix for CVE-2026-40304?

Yes. github.com/openziti/zrok/v2 (Go): upgrade to 2.0.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: Am I affected by CVE-2026-40304?

Check whether you run github.com/openziti/zrok (Go), github.com/openziti/zrok/v2 (Go) or Netfoundry Zrok at an affected version. 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-2026-40304 · Severity: medium · CVSS 5.3 · Published 2026-04-17

zrok is software for sharing web services, files, and network resources. Prior to version 2.0.1, the unaccess handler (controller/unaccess.go) contains a logical error in its ownership guard: when a frontend record has environment_id = NULL (the marker for admin-created global frontends), the condition short-circuits to false and allows the deletion to proceed without any ownership verification. A non-admin user who knows a global frontend token can call DELETE /api/v2/unaccess with any of their own environment IDs and permanently delete the global frontend, taking down all public shares routed through it. Version 2.0.1 patches the issue.

Technologies: github.com/openziti/zrok (Go), github.com/openziti/zrok/v2 (Go), Netfoundry Zrok. Vendors: Go, Netfoundry.

Quick answers

Is CVE-2026-40304 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-40304 being exploited in the wild.
How severe is CVE-2026-40304?: Medium severity, with a CVSS score of 5.3, published 17 April 2026.
Which products and versions are affected?: github.com/openziti/zrok (Go) <= 1.1.11, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.1.11; github.com/openziti/zrok/v2 (Go) < 2.0.1, SEMVER:introduced=0,fixed=2.0.1.
Is there a fix for CVE-2026-40304?: Yes. github.com/openziti/zrok/v2 (Go): upgrade to 2.0.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-40304?: Check whether you run github.com/openziti/zrok (Go), github.com/openziti/zrok/v2 (Go) or Netfoundry Zrok at an affected version. 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.

How to fix

github.com/openziti/zrok/v2 (Go): upgrade to 2.0.1 or later
```
go get github.com/openziti/zrok/v2@v2.0.1
```

Affected products

github.com/openziti/zrok (Go) <= 1.1.11, SEMVER:introduced=0, SEMVER:introduced=0,last_affected=1.1.11
github.com/openziti/zrok/v2 (Go) < 2.0.1, SEMVER:introduced=0,fixed=2.0.1
Netfoundry Zrok

Identifiers

CVE-2026-40304
GHSA-3jpj-v3xr-5h6g
GO-2026-5090

References

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