CVE-2026-86543

knowns versions before 0.30.0 serve the management API without authentication on all network interfaces by default, with no password required on fresh installations. Attackers can access the unauthenticated /api/tunnel/start endpoint to provision a public tunnel and republish the API at a publicly accessible address.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/cli/browser.go#L193-L200
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/auth.go#L80-L86
https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/tunnel.go#L26-L38
https://github.com/knowns-dev/knowns/commit/878a02cb7cc14f0a592fdfda7a520af3cac500fb
https://github.com/knowns-dev/knowns/releases/tag/v0.30.0
https://github.com/knowns-dev/knowns/security/advisories/GHSA-fc85-99vc-9c75
https://www.vulncheck.com/advisories/knowns-before-0.30.0-unauthenticated-management-api-exposure

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 23:16

Updated : 2026-09-14 20:17

NVD link : CVE-2026-86543

Mitre link : CVE-2026-86543

CVE.ORG link : CVE-2026-86543

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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