Vulnerability in node-opcua (CVE-2026-54155)
Summary
Vulnerability in node-opcua (CVE-2026-54155). Confidential information can be exposed externally. Exploitable via session.nonce.
Original description
The description as published by the source.
Summary
A missing nonce verification in the UserNameIdentityToken authentication handler allows an unauthenticated remote attacker to forge a password token that extracts as an empty string, and to replay captured authentication tokens across sessions.
Affected versions: <= 2.165.0
Tested version: 2.165.0
CVSS Score: 8.1 (High)
CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
CWE: CWE-347 Improper Verification of Cryptographic Signature
Root Cause
In packages/node-opcua-server/source/opcua_server.ts at line 1886-1887, after RSA-OAEP decrypting the UserNameIdentityToken password blob, the server reads a 4-byte little-endian length field and extracts buff[4 : 4+length] as the password. It never verifies that the trailing bytes equal session.nonce.
This has two consequences:
-
Forged empty password: An attacker who retrieves the server's public key via an unauthenticated
GetEndpointscall can craft a token where the 4-byte length field equalsserverNonce.length(32). The server computeslength = 32 - 32 = 0and callsisValidUser(username, ""). Any account that accepts an empty password is compromised. -
Unconditional replay attack: Because nonce binding is structurally absent, any captured UserNameIdentityToken ciphertext can be replayed in a different session unconditionally.
The impact is compounded by a second issue: when the channel uses SecurityMode=None, verifyClientSignature returns true uncond…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-54155 has been found in node-opcua.
Attackers can target a specific entry point like session.nonce over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 7.7/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "node-opcua CVE-2026-54155" on the vendor's site.
CVE-2026-54155 (node-opcua) — CWE-347 / CVSS v3 7.7
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: session.nonce / GetEndpoints / serverNonce.length / verifyClientSignature
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-347) exists in node-opcua. Attackers reach the vulnerable code path via session.nonce without authentication.
Check the vendor advisory for the affected versions of node-opcua. Attack surface: session.nonce / GetEndpoints / serverNonce.length / verifyClientSignature.
Severity: High (CVSS 7.7/10). Confidential information can be exposed externally.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'node-opcua' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'node-opcua' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
node-opcuaを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web github.com
- web github.com
- web security-advisories@github.com
- web security-advisories@github.com