GHSA-3JPJ-V3XR-5H6G
Vulnerability from github – Published: 2026-04-16 21:09 – Updated: 2026-04-24 20:49Summary 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)
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/openziti/zrok"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "1.1.11"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/openziti/zrok/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.0.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-40304"
],
"database_specific": {
"cwe_ids": [
"CWE-284",
"CWE-863"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-16T21:09:23Z",
"nvd_published_at": "2026-04-17T22:16:32Z",
"severity": "MODERATE"
},
"details": "Summary\nThe 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.\n\nAttack Vector: Network \u2014 the endpoint is a standard HTTP API call.\n\nAttack Complexity: High \u2014 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).\n\nPrivileges Required: Low \u2014 a valid user account with at least one registered environment is required; no admin privileges needed.\n\nUser Interaction: None.\n\nScope: Unchanged \u2014 the impact stays within the same server instance.\n\nConfidentiality Impact: None \u2014 no data is disclosed.\n\nIntegrity Impact: None \u2014 no data is improperly modified; the record is deleted (not corrupted).\n\nAvailability Impact: High \u2014 deleting a global frontend disrupts every public share routed through it on the instance, constituting a platform-wide availability impact.\n\nAffected Component\ncontroller/unaccess.go \u2014 unaccessHandler.Handle (line 56)",
"id": "GHSA-3jpj-v3xr-5h6g",
"modified": "2026-04-24T20:49:03Z",
"published": "2026-04-16T21:09:23Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/openziti/zrok/security/advisories/GHSA-3jpj-v3xr-5h6g"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40304"
},
{
"type": "PACKAGE",
"url": "https://github.com/openziti/zrok"
},
{
"type": "WEB",
"url": "https://github.com/openziti/zrok/releases/tag/v2.0.1"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "zrok: Broken ownership check in DELETE /api/v2/unaccess allows non-admin to delete global frontend records"
}
Sightings
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