Labs64 NetLicensing MCP Server: REST path traversal bypasses token redaction
Summary
NetLicensing MCP Server passes a caller-supplied product number unvalidated into a REST path. A value containing traversal segments such as "../" is normalized by the HTTP client to the /token endpoint, and the response skips the redaction of APIKEY number and SHOP shopURL fields. An authenticated MCP client with a non-administrative API key can read plaintext token values, and a recovered administrative token grants broad read, write and delete access to the NetLicensing account.
Affected
- Labs64 NetLicensing-MCP versions before 0.1.8
Fixed in
- Version 0.1.8 (fix commit b8fd0ea76d533202573eb24add9fb2fbd9331496). Latest release at time of research: 0.1.10.
Workaround
- No vendor workaround known. Upgrading is the documented remediation.
Exploitation
- CISA SSVC: exploitation status "poc", not automatable.
- Public proof of concept available; no evidence of in-the-wild exploitation found.
- Attacker needs a valid NetLicensing API key that can call MCP tools.
Our recommendation
- Upgrade NetLicensing MCP Server to version 0.1.8 or later.
- Rotate the NetLicensing API keys that the server could reach, as keys may already have been exposed.
- Until patched, restrict which MCP clients can reach the server and limit the API keys it holds.
- Review NetLicensing account activity for unexpected read, write or delete operations.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- GitHub security advisory GHSA-hxpf-9xvq-wph8 github.com
- Fix commit b8fd0ea github.com
- Pull request #6 github.com
- Release 0.1.8 github.com
- OSV GHSA-hxpf-9xvq-wph8 osv.dev
- OpenCVE CVE-2026-57496 app.opencve.io
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 30 Oct 2026, 22:48.
Original description (NVD)
NetLicensing MCP Server is a natural-language interface that enables agentic applications to manage the software-licensing lifecycle in Labs64 NetLicensing. Prior to 0.1.8, netlicensing_get_product passes the caller-controlled product_number to src/netlicensing_mcp/tools/products.py, which interpolates it into a REST path consumed by nl_get() in src/netlicensing_mcp/client.py without path-segment validation. A traversal segment can be normalized from the intended product path to the /token endpoint, after which the response is serialized through _wrap_json instead of _wrap_json_token_read, bypassing redact_token_read() protections for APIKEY number and SHOP shopURL fields. An authenticated MCP client with a non-administrative API key can retrieve plaintext token values, and a recovered administrative token can provide broad read, write, and delete access to the NetLicensing account. This issue is fixed in version 0.1.8.
NVD references (5)
- https://github.com/Labs64/NetLicensing-MCP/commit/b8fd0ea76d533202573eb24add9fb2fbd9331496
- https://github.com/Labs64/NetLicensing-MCP/pull/6
- https://github.com/Labs64/NetLicensing-MCP/releases/tag/0.1.8
- https://github.com/Labs64/NetLicensing-MCP/security/advisories/GHSA-hxpf-9xvq-wph8
- https://github.com/Labs64/NetLicensing-MCP/security/advisories/GHSA-hxpf-9xvq-wph8
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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