{"id":"CVE-2026-54156","summary":"node-opcua: Unbounded nonce cache enables unauthenticated heap exhaustion DoS","details":"node-opcua is an OPC UA implementation for TypeScript and Node.js. Prior to 2.166.0, the process-global g_alreadyUsedNonce cache used by nonceAlreadyBeenUsed in packages/node-opcua-secure-channel/source/server/server_secure_channel_layer.ts records nonces from OpenSecureChannelRequest and CreateSession without expiration or a size limit. An unauthenticated remote attacker can repeatedly create sessions with unique nonces, causing entries to persist after session expiry and accumulate across connection cycles even when maxSessions=10 limits concurrent sessions. The resulting unbounded heap growth can exhaust the default Node.js heap and crash the node-opcua server process. This issue is fixed in version 2.166.0.","aliases":["GHSA-6wvw-vrw4-363w"],"modified":"2026-09-16T03:46:30.149567601Z","published":"2026-09-14T16:09:07.744Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-770"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54156.json"},"references":[{"type":"WEB","url":"https://github.com/node-opcua/node-opcua/releases/tag/v2.166.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54156.json"},{"type":"ADVISORY","url":"https://github.com/node-opcua/node-opcua/security/advisories/GHSA-6wvw-vrw4-363w"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54156"},{"type":"FIX","url":"https://github.com/node-opcua/node-opcua/commit/b82c2939fe9c658de58da993f2798ec5481d7313"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/node-opcua/node-opcua","events":[{"introduced":"0"},{"fixed":"b82c2939fe9c658de58da993f2798ec5481d7313"},{"fixed":"b50d48c0ebd4761670529bf66f39a9c402a07845"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"2.166.0"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v2.165.2","v2.165.1","v2.165.0","v2.164.2","v2.164.1","v2.164.0","v2.163.1","v2.163.0","v2.162.0","v2.161.0","v2.160.0","v2.159.0","v2.158.0","v2.157.0","v2.156.0","v2.155.0","v2.154.0","v2.153.0","v2.152.0","v2.151.0","v2.150.0","v2.149.0","v2.148.0","v2.147.0","v2.146.0","v2.145.0","v2.144.0","v2.143.0","v2.142.0","v2.141.0","v2.140.0","v2.139.0","v2.138.1","v2.138.0","v2.137.0","v2.136.0","v2.135.0","v2.134.0","v2.133.0","v2.132.0","v2.131.0","v2.130.0","v2.129.0","v2.128.0","v2.127.1","v2.127.0","v2.126.0","v2.125.0","v2.124.0","v2.123.0","v2.122.0","v2.121.0","v2.120.0","v2.119.2","v2.119.1","v2.119.0","v2.113.0","v2.118.0","v2.117.0","v2.116.0","v2.115.0","v2.114.0","v2.112.0","v2.111.0","v2.110.0","v2.109.0","v2.108.0","v2.107.0","v2.106.0","v2.105.1","v2.105.0","v2.104.0","v2.103.0","v2.102.0","v2.101.0","v2.100.0","v2.99.1","v2.99.0","v2.98.2","v2.98.1","v2.98.0","v2.97.0","v2.96.0","v2.95.0","v2.94.0","v2.93.0","v2.92.0","v2.91.1","v2.91.0","v2.90.1","v2.90.0","v2.89.0","v2.88.0","v2.87.0","v2.86.1","v2.86.0","v2.85.0","v2.84.0","v2.83.0","v2.82.0","v2.81.0","v2.80.1","v2.80.0","v2.79.1","v2.79.0","v2.78.0","v2.77.0","v2.76.2","v2.76.1","v2.76.0","v2.75.0","v2.74.0","v2.73.1","v2.73.0","v2.72.2","v2.72.1","v2.72.0","v2.71.0","v2.70.3","v2.70.2","v2.70.1","v2.70.0","v2.69.1","v2.69.0","v2.67.0","v2.68.1","v2.68.0","v2.66.3","v2.66.2","v2.66.1","v2.66.0","v2.65.1","v2.65.0","v2.64.1","v2.64.0","v2.63.2","v2.63.1","v2.63.0","v2.62.7","v2.62.6","v2.62.5","v2.62.4","v2.62.3","v2.62.2","v2.62.1","v2.62.0","v2.61.0","v2.60.2","v2.60.1","v2.60.0","v2.59.1","v2.59.0","v2.58.0","v2.57.0","v2.56.3","v2.56.2","v2.56.1","v2.56.0","v2.55.0","v2.52.0","v2.51.0","v2.50.0","v2.49.0","v2.47.0","v2.46.0","v2.45.0","v2.44.0","v2.43.0","v2.42.2","v2.42.1","v2.42.0","v2.41.1","v2.41.0","v2.40.0","v2.37.0","v2.36.3","v2.36.2","v2.36.1","v2.36.0","v2.35.0","v2.34.0","v2.33.0","v2.32.0","v2.31.0","v2.30.0","v2.29.0","v2.28.3","v2.28.2","v2.28.1","v2.28.0","v2.27.1","v2.27.0","v2.26.0","v2.25.0","v2.24.1","v2.24.0","v2.23.0","v2.22.0","v2.21.0","v2.20.0","v2.19.0","v2.18.0","v2.17.0","v2.16.0","v2.15.0","v2.14.0","v2.13.0","v2.12.0","v2.11.0","v2.10.0","v2.9.1","v2.9.0","v2.8.1","v2.8.0","v2.7.0","v2.6.7","v2.6.6","v2.6.5","v2.6.4","v2.6.3","v2.6.2","v2.6.1","v2.6.0-alpha.7","v2.6.0-alpha.6","v2.6.0-alpha.1","v2.6.0-alpha.0","v2.5.12","v2.5.11","v2.5.10","v2.5.9","v2.5.8","v2.5.7","v2.5.6","v2.5.5","v2.5.4","v2.5.3","v2.5.2","v2.5.1","v2.5.0-alpha.15","v2.5.0-alpha.14","v2.5.0-alpha.13","v2.5.0-alpha.12","v2.5.0-alpha.11","v2.5.0-alpha.10","v2.5.0-alpha.9","v2.5.0-alpha.8","v2.5.0-alpha.7","v2.5.0-alpha.6","v2.5.0-alpha.5","v2.5.0-alpha.4","v2.5.0-alpha.3","v2.5.0-alpha.2","v2.5.0-alpha.1","v2.5.0-alpha.0","v2.4.4","v2.4.3","v2.4.2","v2.4.1","v2.4.0","v2.3.1","v2.3.0","v2.2.0","v2.1.9","v2.1.8","v2.1.7","v2.1.6","v2.1.5","v2.1.2","v2.1.1","v2.1.0","v2.0.1","v2.0.0","v2.0.0-alpha.33","v2.0.0-alpha.32","v2.0.0-alpha.31","v2.0.0-alpha.30","v2.0.0-alpha.29","v2.0.0-alpha.28","v2.0.0-alpha.27","v2.0.0-alpha.26","v2.0.0-alpha.25","v2.0.0-alpha.24","v2.0.0-alpha.23","v2.0.0-alpha.22","v2.0.0-alpha.21","v2.0.0-alpha.20","v2.0.0-alpha.19","v2.0.0-alpha.18","v2.0.0-alpha.17","v2.0.0-alpha.16","v2.0.0-alpha.15","v2.0.0-alpha.14","v2.0.0-alpha.13","v2.0.0-alpha.11","v2.0.0-alpha.10","v2.0.0-alpha.9","v2.0.0-alpha.8","v2.0.0-alpha.7","v2.0.0-alpha.6","v2.0.0-alpha.5","v2.0.0-alpha.4","v2.0.0-alpha.0","v0.4.5","v0.4.4","v0.4.3","v0.4.2","v0.4.1","v0.4.0","v0.3.0","v0.2.3","v0.2.2","v0.2.1","v0.2.0","V0.2.0","v0.1.1-0","v0.1.0-13","v0.1.0-12","v0.1.0-11","v0.1.0-10","v0.1.0-9","v0.1.0-8","v0.1.0-7","v0.1.0-6","v0.1.0-5","v0.1.0-4","v0.0.65","v0.0.64","v0.0.61","v0.0.60","v0.0.59","v0.0.58","v0.0.57","v0.0.56b","v0.0.56","v0.0.55","v0.0.54","v0.0.53","v.0.0.53","v0.0.52","v0.0.51","v0.0.50","v0.0.49","v0.0.48","v0.0.47","v0.0.46","v0.0.45","0.0.45","v0.0.42","v0.0.41","v0.0.40","v0.0.39","v0.0.38","v0.0.37","v0.0.35","v0.0.34","v0.0.24","v0.0.23","v0.0.22","v0.0.21","v0.0.20","v0.0.19","v0.0.14","v0.0.11","0.0.8","0.0.7","v0.0.5","v0.0.4","v0.0.3"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54156.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}