Vulnerability · Published Sep 14, 2026 · Assigned by GitHub_M
CVE-2026-54155node-opcua: Missing nonce verification in UserNameIdentityToken authentication
High 7.7
In plain English
A high-severity security flaw in node-opcua from node-opcua. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities).
Official description
node-opcua is an OPC UA implementation for TypeScript and Node.js. Prior to 2.166.0, the UserNameIdentityToken authentication handler in packages/node-opcua-server/source/opcua_server.ts decrypts an RSA-OAEP password blob but does not verify that the trailing bytes match the current session serverNonce. An unauthenticated remote attacker can obtain the server public key through GetEndpoints and forge a blob whose little-endian length produces an empty password passed to isValidUser, compromising accounts that accept an empty password. Missing nonce binding also allows a captured UserNameIdentityToken ciphertext to be replayed in another session, and SecurityMode=None removes the separate client-signature safeguard. This issue is fixed in version 2.166.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | node-opcua | no fix listed | GHSA-mq36-523m-x7vv |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| node-opcua | node-opcua | < 2.166.0 |
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L