nebula-mesh is a self-hosted control plane for Slack Nebula mesh virtual private network. Prior to version 0.3.3, every /ui/* POST / PUT / PATCH / DELETE route processes the request as soon as the session cookie validates. SameSite=Lax on the session cookie prevents most cross-site form submits but does not protect: top-level form-submit navigations from third-party pages (some browsers still send Lax cookies on top-level POSTs); same-registrable-domain attackers (sibling-subdomain XSS, subdomain takeover); the GET /ui/logout route, which a third-party <img src=".../ui/logout"> can force-trigger.
This issue has been patched in version 0.3.3.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v4.0