7.7High

CVE-2026-63464

nebula-mesh is a self-hosted control plane for Slack Nebula mesh VPN. From version 0.6.0 to before version 0.7.2, non-admin operators (role user) can set allow_private: true on their own managed webhook subscription (POST/PATCH /api/v1/webhook-subscriptions). No admin check exists on this field. At delivery time, allow_private switches the dispatcher to an unguarded HTTP client, bypassing the private/loopback/link-local SSRF guard — letting a low-privilege operator make the server request internal addresses. This issue has been patched in version 0.7.2.

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 0.3% chance of attack attempts being seen in the next 30 days, ranking above 18% 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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CVE-2026-63464

What this means for your business

What to do

Not sure if your company is exposed to CVE-2026-63464?

Scoring

Dates

References