CVE-2026-86543

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.85% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 58.1% of scored records. A rank, not a probability.

NVD base score

9.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-09-14.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-09-07 23:03Z1 MO AGO

Last updated

2026-09-24 14:21Z1 MO AGO

Reserved

2026-09-07

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Critical (CVSS 9.3)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Weaknesses

• CWE-306Missing Authentication for Critical FunctionBase

Data version

5.2

Document digest

4b5562034a7995c1206e569e13d9abb1c936029482a07b020f7164a1de0f2aff

• github.comGitHub Security Advisory (GHSA-fc85-99vc-9c75)https://github.com/knowns-dev/knowns/security/advisories/GHSA-fc85-99vc-9c75vendor-advisory
• github.comAuthManager.Middleware is a no-op when no password is configured (v0.29.1)https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/auth.go#L80-L86technical-description
• github.comBrowser listener binds 0.0.0.0 (v0.29.1)https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/cli/browser.go#L193-L200technical-description
• github.comPOST /api/tunnel/start has no authorization check of its own (v0.29.1)https://github.com/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/tunnel.go#L26-L38technical-description
• github.comknowns fix commit 878a02cb7cc1https://github.com/knowns-dev/knowns/commit/878a02cb7cc14f0a592fdfda7a520af3cac500fbpatch
• github.comknowns v0.30.0 Release Noteshttps://github.com/knowns-dev/knowns/releases/tag/v0.30.0release-notes
• www.vulncheck.comVulnCheck Advisory: knowns before 0.30.0 Unauthenticated Management API Exposurehttps://www.vulncheck.com/advisories/knowns-before-0.30.0-unauthenticated-management-api-exposurethird-party-advisory