What’s Vulnerable › Vulnerabilities

CVE-2026-86543: knowns before 0.30.0 Unauthenticated Management API Exposure

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-07 · updated 2026-09-14
• Weakness: CWE-306

Description

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.

Affected products

• knowns-dev knowns: before 0.30.0 — fixed in 0.30.0

How to fix

Upgrade to a fixed version: knowns-dev knowns 0.30.0. Check the vendor advisory for mitigations.

References

• 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

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