CVE-2026-63464

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure.

Exploit odds

0.5% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-04 20:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-08 21:05 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.5% in the next 30 days (EPSS).
• Severity: 7.7 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-09-04 20:17 UTC

Last modified

2026-09-08 21:05 UTC

Exploit probability

0.5% · EPSS, next 30 days

Weakness

CWE-862 · Missing authorization

Record status

Deferred

Attack profile CVSS 3.1 · 7.7

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Changed

Confidentiality

High

Integrity

None

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-63464.md and follow it. Check whether this project is affected by CVE-2026-63464. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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