nebula-mesh: Web UI host creation ignores configured enrollment token TTL and mints 24-hour bearer enrollment tokens

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.4 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

EPSS

• CVE-2026-55513: 0.32% estimated exploitation activity in the next 30 days; percentile 25.04 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The nebula-mgmt Web UI host-creation path ignores both the server-wide enrollmenttokenttl security setting and per-network networkconfig.enrollmenttokenttl overrides. API host creation and token-regeneration paths use the configured TTL resolver, but POST /ui/hosts hardcodes now.Add(24 time.Hour) for newly minted agent enrollment tokens. In deployments that intentionally reduce enrollment-token lifetime, any authenticated operator who can create a host through the Web UI can still mint a bearer enrollment token valid for about 24 hours. Details Enrollment tokens are bearer credentials for the public POST /api/v1/enroll endpoint: possession of a valid token allows enrolling the pending host and receiving a signed Nebula certificate/config for that host. The server configuration documents a security knob for their default lifetime and per-network overrides: - internal/config/server.go:82 defines EnrollmentTokenTTL as the default lifetime for freshly minted enrollment tokens. -…

Published by the source

14 Jul 2026, 20:26 UTC

Last modified by the source

14 Jul 2026, 20:26 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-g4x6-jcvr-9m3g

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# Patch Next advisory brief: CVE-2026-55513

Advisory: nebula-mesh: Web UI host creation ignores configured enrollment token TTL and mints 24-hour bearer enrollment tokens
IDs: CVE-2026-55513, GHSA-g4x6-jcvr-9m3g
Record: https://patchnext.com/advisories/cve-2026-55513 (revision 1, source checked 26 Oct 2026, 15:24 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/forgekeep/nebula-mesh 0.5.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/forgekeep/nebula-mesh: affected >= 0.3.0, < 0.5.0; fixed in 0.5.0

## Suggested inspection (read-only)
- Go github.com/forgekeep/nebula-mesh: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/forgekeep/nebula-mesh.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-g4x6-jcvr-9m3g (GitHub-reviewed advisory GHSA-g4x6-jcvr-9m3g lists affected ranges: Go github.com/forgekeep/nebula-mesh >=0.3.0 <0.5.0)

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