High 7.5Published Sep 14, 2026

CVE-2026-54156node-opcua: Unbounded nonce cache enables unauthenticated heap exhaustion DoS

Updated under an hour ago (2026-10-19 09:20 UTC)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for node-opcua

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Awaiting Analysis
Record last updated: Sep 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

node-opcua node-opcua node_opcua:node_opcua (from the name)	before 2.166.0	CNA record

References

https://github.com/node-opcua/node-opcua/security/advisories/GHSA-6wvw-vrw4-363wx-refsource-confirm
https://github.com/node-opcua/node-opcua/commit/b82c2939fe9c658de58da993f2798ec5481d7313x-refsource-misc
https://github.com/node-opcua/node-opcua/releases/tag/v2.166.0x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.