{"id":"CVE-2026-54156","revision":"18d0d000b50e486da7689fe5a748e48e","records":[{"revision":"18d0d000b50e486da7689fe5a748e48e","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-54156","aliases":[],"title":"node-opcua: Unbounded nonce cache enables unauthenticated heap exhaustion DoS","description":"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.","state":0,"publishedAt":"2026-09-14T16:09:07.744+00:00","modifiedAt":"2026-09-14T16:35:48.958+00:00","affected":[{"ecosystem":"Vendor product","name":"node-opcua","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"node-opcua\",\n                    \"product\": \"node-opcua\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 2.166.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/node-opcua/node-opcua/security/advisories/GHSA-6wvw-vrw4-363w","https://github.com/node-opcua/node-opcua/commit/b82c2939fe9c658de58da993f2798ec5481d7313","https://github.com/node-opcua/node-opcua/releases/tag/v2.166.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-54156","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-54156","identifiers":["CVE-2026-54156"]},"retained":false,"historicalAffected":[]}],"coverage":[]}