CVE-2026-54155

CVE-2026-54155

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L.

EPSS exploit prediction

EPSS: 0.004 (36.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 36.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-54155: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-54155?
CVE-2026-54155 is a high-severity vulnerability, classified under Improper Verification of Cryptographic Signature. CVSS score: 7.7/10. Published 2026-09-14.
How severe is CVE-2026-54155?
High severity. CVSS v3 base score is 7.7 out of 10.