CVSS v3
7.7
HIGH
EPSS Score
0.5 %
exploit probability, as of 2026-09-28
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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 intern
Technical details
- Published
- 2026-09-04
- Last Modified
- 2026-09-04
Frequently asked questions
What is 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 intern
Is CVE-2026-63464 actively exploited?
Active exploitation of CVE-2026-63464 has not been confirmed. Its EPSS score was 0.5% on 2026-09-28, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2026-63464?
CVE-2026-63464 has a CVSS v3 base score of 7.7 (HIGH severity).
Is CVE-2026-63464 affecting your environment?
Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.
No credit card required · 500 free checks/month · Free API key
Other 2026 vulnerabilities worth triaging
Ranked by exploit probability (EPSS).
- CVE-2026-10520KEV
- CVE-2026-24061KEV
- CVE-2026-1281KEV
- CVE-2026-1340KEVUnauthenticated Remote Code Execution via Code Injection in Ivanti Endpoint Manager Mobile
- CVE-2026-41940KEV
- CVE-2026-23760KEVSmarterTools SmarterMail < Build 9511 Authentication Bypass via Password Reset API
- CVE-2026-21643KEVSQL Injection Vulnerability in FortiClientEMS 7.4.4 Allows Unauthenticated Remote Code Execution
- CVE-2026-20182KEV