vulnerability / NVI-00013917 / Revision 1
node-opcua: Unbounded nonce cache enables unauthenticated heap exhaustion DoS
GitHub lists this reviewed advisory for node-opcua. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
7.5 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
node-opcua
source listed< 2.166.0
**Summary** A process-global nonce cache with no eviction policy allows an unauthenticated remote attacker to exhaust server heap memory by repeatedly opening sessions, causing the node-opcua server process to crash. **Affected versions:** <= 2.165.0 **Tested version:** 2.165.0 **CVSS Score:** 7.5 (High) **CVSS Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H **CWE:** CWE-770 Allocation of Resources Without Limits or Throttling --- **Root Cause** In `packages/node-opcua-secure-channel/source/server/server_secure_channel_layer.ts` at line 156, `g_alreadyUsedNonce` is a process-global object used to track previously seen nonces for replay detection. Entries are added on every `OpenSecureChannelRequest` and every `CreateSession` request but are never removed or expired. An unauthenticated attacker can exploit the `CreateSession` path (which requires no certificate) to accumulate nonce entries indefinitely. Even with `maxSessions=10` limiting concurrent sessions, nonces persist after session expiry, allowing slow but reliable heap exhaustion across repeated connection cycles. --- **Measured Impact** Dynamically confirmed heap growth: - 5,000 unique nonces → +1.23 MB resid
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-6wvw-vrw4-363w ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.