GitHub Advisoryadvisory · Go

GHSA-3jpj-v3xr-5h6g zrok: Broken ownership check in DELETE /api/v2/unaccess allows non-admin to delete global frontend records

MEDIUM Published 2026-04-16 Modified 2026-04-24 Official page ↗
Aliases
CVE-2026-40304
Ecosystem
Go
Packages
github.com/openziti/zrok, github.com/openziti/zrok/v2
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-284, CWE-863
Reviewed
2026-04-16

Affected packages

• Go github.com/openziti/zrok: <= 1.1.11 (no fix yet) • Go github.com/openziti/zrok/v2: < 2.0.1 → fixed in 2.0.1

Description

Summary 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. Attack Vector: Network — the endpoint is a standard HTTP API call. Attack Complexity: High — successful exploitation requires prior knowledge of a global frontend token. These tokens are not returned to non-admin users by any standard API endpoint; obtaining one requires an out-of-band step (e.g., leaked server logs, admin documentation for a self-hosted instance, or social engineering). Privileges Required: Low — a valid user account with at least one registered environment is required; no admin privileges needed. User Interaction: None. Scope: Unchanged — the impact stays within the same server instance. Confidentiality Impact: None — no data is disclosed. Integrity Impact: None — no data is improperly modified; the record is deleted (not corrupted). Availability Impact: High — deleting a global frontend disrupts every public share routed through it on the instance, constituting a platform-wide availability impact. Affected Component controller/unaccess.go — unaccessHandler.Handle (line 56)

Related

Alias · CVE (1)

  • CVE-2026-40304 zrok is software for sharing web services, files, and network resources. vulnerability

Weakness · CWE (2)

  • CWE-284 Improper Access Control weakness
  • CWE-863 Incorrect Authorization weakness

References