{"id":"CVE-2026-54156","sourceIdentifier":"security-advisories@github.com","published":"2026-09-14T17:17:46.927","lastModified":"2026-09-30T19:38:27.293","vulnStatus":"Awaiting Analysis","cveTags":[],"descriptions":[{"lang":"en","value":"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."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"node-opcua","product":"node-opcua","versions":[{"version":"< 2.166.0","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-14T16:35:36.222019Z","id":"CVE-2026-54156","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Primary","description":[{"lang":"en","value":"CWE-770"}]}],"references":[{"url":"https://github.com/node-opcua/node-opcua/commit/b82c2939fe9c658de58da993f2798ec5481d7313","source":"security-advisories@github.com"},{"url":"https://github.com/node-opcua/node-opcua/releases/tag/v2.166.0","source":"security-advisories@github.com"},{"url":"https://github.com/node-opcua/node-opcua/security/advisories/GHSA-6wvw-vrw4-363w","source":"security-advisories@github.com"}]}