Netmaker does not verify JWT signatures for host tokens

CVE-2026-38651 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

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.

Basic information

Type
reviewed
Severity
critical
Advisory on GitHub
Open advisory ↗
Repository advisory
—
Source code
Browse source ↗
Published (advisory)
2026-04-28 18:30:33 UTC
Updated
2026-05-05 14:45:58 UTC
GitHub reviewed
2026-05-05 14:45:55 UTC
NVD published
2026-04-28 16:16:13 UTC

EPSS Score

Score Percentile
0.03% 7.95%

CVSS Scores

Base score Version Severity Vector
8.2 3.1 —
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
9.2 4.0 —
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:H)
High confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:L)
Limited integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:H)
High confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:L)
Limited integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.

Identifiers

Type Value
GHSA GHSA-qpv2-rwc8-c993 ↗
CVE CVE-2026-38651 ↗

CWEs

CWE id Name
CWE-347 Improper Verification of Cryptographic Signature

Credits

  • rvizx (analyst)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
go github.com/gravitl/netmaker < 1.5.0 1.5.0 —

References

cvelogic Threat Intelligence