CVE-2026-86543 json
knowns before 0.30.0 Unauthenticated Management API Exposure
published 2mo ago modified last mo. also EUVD-2026-72561 , GHSA-fc85-99vc-9c75
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository knowns-dev/knowns. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 58%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm knowns 0.30.0
- knowns-dev knowns 0.30.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- last mo.
Exploit prediction
0.86% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.3 | 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 |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.3 | 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 |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | knowns | <=0.29.1 |
0.30.0 |
Affected products
- knowns-dev knowns
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
-
github.com
/knowns-dev/knowns/commit/878a02cb7cc14f0a592fdfda7a520af3cac500fb
patch
-
github.com
/knowns-dev/knowns/security/advisories/GHSA-fc85-99vc-9c75
vendor-advisory, advisory
-
github.com
/knowns-dev/knowns/blob/v0.29.1/internal/server/auth.go#L80-L86
technical-description
-
github.com
/knowns-dev/knowns/blob/v0.29.1/internal/cli/browser.go#L193-L200
technical-description
-
github.com
/knowns-dev/knowns/blob/v0.29.1/internal/server/routes/tunnel.go#L26-L38
technical-description
-
github.com
/knowns-dev/knowns/releases/tag/v0.30.0
release-notes
-
vulncheck.com
/advisories/knowns-before-0.30.0-unauthenticated-management-api-exposure
third-party-advisory
Sources
- CVE List CVE-2026-86543
- NVD CVE-2026-86543
- Maintainer advisory GHSA-fc85-99vc-9c75
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of knowns-dev/knowns published their own advisory on GitHub. Reviewed sources take precedence over it.