CVE-2026-55513
nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. From version 0.3.0 to before version 0.5.0, the nebula-mgmt Web UI host-creation path ignores both the server-wide enrollment_token_ttl security setting and per-network network_config.enrollment_token_ttl 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. This issue has been patched in version 0.5.0.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 8% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 5.4 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N- Weakness
- CWE-613
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-04
- Last modified
- 2026-09-08
- Sources
- NVD
References
- https://github.com/forgekeep/nebula-mesh/commit/514006029e09f1991122b86a80e7b25970bcfa98
- https://github.com/forgekeep/nebula-mesh/releases/tag/v0.5.0
- https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-g4x6-jcvr-9m3g
- https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-g4x6-jcvr-9m3g