CVE-2026-38651 is a high-severity (CVSS 8.2) CWE-347 vulnerability in github.com/gravitl/netmaker. A fix is available for github.com/gravitl/netmaker — see the affected versions and patch details below.
Netmaker does not verify JWT signatures for host tokens
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-2026-38651 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 377,636 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
github.com/gravitl/netmakerReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Netmaker by Gravitl is an open-source WireGuard-based networking platform for creating and managing virtual overlay networks. The VerifyHostToken function in logic/jwts.go does not validate the JWT signature when verifying host tokens. After calling jwt.ParseWithClaims, the function only checks whether the returned token object is non-nil. It does not check token.Valid or the returned error. An attacker can forge a JWT signed with any key, set the claims to any host ID, and pull that host's full configuration including bcrypt-hashed passwords, MQTT credentials, and WireGuard peer data. The issue was patched in v1.5.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/gravitl/netmaker | all versions | 1.5.0go get github.com/gravitl/netmaker@v1.5.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/gravitl/netmaker, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/gravitl/netmaker to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-38651 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-2026-38651 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-38651. 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-2026-38651 in your dependencies?
O3 Security finds CVE-2026-38651 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.