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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products
forgekeep:nebula-mesh
References 3
https://github.com/forgekeep/nebula-mesh/commit/f3c54530e388dd21763e548923426e6…
security-advisories@github.com
https://github.com/forgekeep/nebula-mesh/releases/tag/v0.7.2
security-advisories@github.com
https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-7rx3-5wx3-5v76
security-advisories@github.com