Access Control Flaw in MCPHub Affects Server Group Permissions
CVE-2026-79746

8.1HIGH

Key Information:

Vendor

Samanhappy

Status
Mcphub
Vendor
CVE Published:
31 August 2026

What is CVE-2026-79746?

MCPHub, a central management hub for multiple MCP servers and APIs, contains a significant access control vulnerability wherein a bearer key configured with accessType: 'servers' or 'custom' can inadvertently grant broader access to server groups. This occurs because the system authorizes access for any single server within a group if it appears on the bearer key’s allowedServers list, neglecting to verify the entire list once the group-level connection is established. Consequently, a key scoped for just one server could allow unrestricted access to all servers in the same group, including those not originally designated for access. The vulnerability has been remedied in version 1.0.31.

Affected Version(s)

mcphub < 1.0.31

References

https://github.com/samanhappy/mcphub/security/advisories/...
x_refsource_CONFIRM
https://github.com/samanhappy/mcphub/pull/1059
x_refsource_MISC
https://github.com/samanhappy/mcphub/commit/2b10ae36112ce...
x_refsource_MISC

CVSS V3.1

Score:
8.1
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.