NetLicensing-MCP: Missing Authentication for Critical Functionality
CVE-2026-54446 is a high-severity missing authentication for critical functionality vulnerability in NetLicensing-MCP from Labs64, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected NetLicensing-MCP versions: < 0.1.6. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.62% chance of exploitation within 30 days, higher than 50% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of NetLicensing-MCP you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Labs64 | NetLicensing-MCP | < 0.1.6 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
NetLicensing MCP Server is a natural-language interface that enables agentic applications to manage the software-licensing lifecycle in Labs64 NetLicensing. Prior to 0.1.6, network-reachable HTTP transport requests to /mcp that omit x-netlicensing-api-key, Authorization: Bearer, and the apikey query parameter pass through ApiKeyMiddleware in src/netlicensing_mcp/server.py without authentication. The downstream api_key_ctx in src/netlicensing_mcp/client.py then falls back to the operator's NETLICENSING_API_KEY and authenticates upstream NetLicensing REST API calls under the operator account. An unauthenticated attacker can invoke MCP tools to enumerate products, licenses, licensees, and transactions, create or modify licensing objects, perform validations, and execute destructive delete operations. The issue affects HTTP deployments configured with a server-side key and does not require user interaction. This issue is fixed in version 0.1.6.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Authentication for Critical Functionality
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
- When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.
More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in NetLicensing-MCP
- 9.6 Critical severity
Recent Missing Authentication for Critical Functionality vulnerabilities
- 9.1 Critical severity
- 9.8 Critical severity
- 9.4 Critical severity
- 8.8 High severity
- 8.6 High severity
- 9.8 Critical severity
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