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TI-2026-45231 Aliases CVE-2026-63464

Nebula-mesh allows non-admin operators to disable webhook SSRF protection via `allow_private`

Priority HIGH 67CWE-862Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass, Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-862, CWE-918 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00464 40th percentileScored 2026-11-07
Fix Fixed nebula-mesh (forgekeep): 0.7.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
forgekeepnebula-mesh0.6.0 to before 0.7.20.7.2Patch availableCNA
  • nebula-mesh Vendorforgekeep Affected 0.6.0 to before 0.7.2 Fixed in 0.7.2 Patch available CNA

Remediation

  • Fix · CNA nebula-mesh (forgekeep) Fixed in 0.7.2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-63464

References

Other 3

  • TI-2026-44169 nebula-mesh: Certificate revocation is never enforced at the mesh CVSS 3.1HIGH 8.1
  • TI-2026-40058 nebula-mesh: Unauthenticated OIDC login endpoint allocates unbounded in-memory state entries without rate limiting CVSS 3.1MEDIUM 5.3
  • TI-2026-40059 nebula-mesh: Web UI host creation ignores configured enrollment token TTL and mints 24-hour bearer enrollment tokens CVSS 3.1MEDIUM 5.4
  • TI-2026-38659 nebula-mesh: Operator session tokens stored in plaintext in the database CVSS 4.0HIGH 7.1
  • TI-2026-38660 nebula-mesh: CA private key not zeroized on web mobile-bundle error paths CVSS 4.0HIGH 7.1
  • TI-2026-38658 nebula-mesh - Host revocation is not durable: blocked/offboarded hosts can regain a valid certificate CVSS 4.0MEDIUM 6.9

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences