CVE-2026-68904 is a high-severity (CVSS 7) Uncontrolled Resource Consumption vulnerability in node-opcua-transport. A fix is available for node-opcua-transport — see the affected versions and patch details below.
node-opcua: TCP Socket Leak (FIN-WAIT-2) via keepalive reconnection cycle - Resource Exhaustion
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-68904.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-68904 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 374,847 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
node-opcua-transport📦node-opcua-client📦node-opcuaReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
node-opcua is an OPC UA implementation for TypeScript and Node.js. From 2.0.0 until 2.170.0, node-opcua clients using the default keepSessionAlive setting can enter a repeated reconnection cycle when an OPC UA server's clock skew causes BadInvalidTimestamp responses. ClientSessionKeepAliveManager._ping_server treated the server-originated ServiceFault as a network outage and forced a transport reconnect, while ClientTCP_transport._on_ACK_response used socket.end() after failed HEL/ACK negotiation and could leave the connection in FIN-WAIT-2 when the peer did not close. Repetition at the keepAliveInterval accumulates file descriptors and memory until the client process or container can be terminated by resource exhaustion. This issue is fixed in version 2.170.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | node-opcua-transport | ≥ 2.0.0&&< 2.170.0 | 2.170.0npm install node-opcua-transport@2.170.0 |
| 📦npm | node-opcua-client | ≥ 2.0.0&&< 2.170.0 | 2.170.0npm install node-opcua-client@2.170.0 |
| 📦npm | node-opcua | ≥ 2.0.0&&< 2.170.0 | 2.170.0npm install node-opcua@2.170.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for node-opcua-transport, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update node-opcua-transport to 2.170.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-68904 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-68904 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-68904. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-68904 in your dependencies?
O3 Security finds CVE-2026-68904 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.