node-opcua: Namespace-Level RBAC Fail-Open - Anonymous Write/Call Bypass via Unbound `DefaultRolePermissions

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.1 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS

• CVE-2026-95860: 0.60% estimated exploitation activity in the next 30 days; percentile 48.83 (FIRST EPSS, 2026-11-10). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary An unauthenticated (Anonymous) client can Write protected Variables and Call privileged Methods on any Node that lacks explicit per-node permissions. This follows the inheritance model defined by OPC UA Part 3, §5.2.9, where nodes without an explicit `RolePermissions` attribute inherit the namespace `DefaultRolePermissions`. OPC 10000-3 §4.8.3 mandates a default-deny evaluation (`Bad_UserAccessDenied` when the operation bits are not set); `node-opcua` instead grants all permissions. The root cause is a combination of an authorization fail-open and a disconnect between the configuration API and the runtime enforcement path. ---

Affected configuration This advisory covers two cases that are not equally severe: 1. No RolePermissions declared anywhere - resolution is permissive. This is node-opcua's documented behaviour for a server with no access control configured, so nothing is being bypassed. Worth fixing as an insecure default (CWE-1188),…

Published by the source

10 Nov 2026, 15:56 UTC

Last modified by the source

10 Nov 2026, 16:15 UTC

Source last checked

11 Nov 2026, 06:00 UTC

1. Revision 2 · amended · 11 Nov 2026

   Amended from osv record GHSA-xggf-m53x-jc3f

2. Revision 1 · created · 10 Nov 2026

   Published from ghsa record GHSA-xggf-m53x-jc3f

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# Patch Next advisory brief: CVE-2026-95860

Advisory: node-opcua: Namespace-Level RBAC Fail-Open - Anonymous Write/Call Bypass via Unbound `DefaultRolePermissions
IDs: CVE-2026-95860, GHSA-xggf-m53x-jc3f
Record: https://patchnext.com/advisories/cve-2026-95860 (revision 2, source checked 11 Nov 2026, 06:00 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: node-opcua-server 2.180.0; node-opcua 2.180.0; node-opcua-address-space 2.180.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm node-opcua-server: affected >= 2.42.0, < 2.180.0; fixed in 2.180.0
- npm node-opcua: affected >= 2.42.0, < 2.180.0; fixed in 2.180.0
- npm node-opcua-address-space: affected >= 2.42.0, < 2.180.0; fixed in 2.180.0

## Suggested inspection (read-only)
- `npm ls node-opcua-server --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.
- `npm ls node-opcua --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.
- `npm ls node-opcua-address-space --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on node-opcua-server, node-opcua, node-opcua-address-space.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-xggf-m53x-jc3f (GitHub-reviewed advisory GHSA-xggf-m53x-jc3f lists affected ranges: npm node-opcua >=2.42.0 =2.42.0 =2.42.0 <2.180.0)
- Verified: https://osv.dev/vulnerability/GHSA-xggf-m53x-jc3f (OSV record GHSA-xggf-m53x-jc3f lists affected ranges: npm node-opcua >=2.42.0 =2.42.0 =2.42.0 <2.180.0 (fixed))

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