CVE-2026-79746CWE-863broken-access-control

CVE-2026-79746

High · published August 31, 2026

CVSS v3.1
8.1
EPSS
0%
Percentile
35.8
In the wild
Unconfirmed
What it is

MCPHub is a unified hub for centrally managing and dynamically orchestrating multiple MCP servers/APIs into separate endpoints with flexible routing strategies. Prior to version 1.0.31, when a bearer key with accessType: 'servers' (or 'custom') is used against a group route, isBearerKeyAllowedForRequest grants access to the entire group as long as any single server in that group appears in the key's allowedServers list — not only when every server the key is scoped to matches, and critically, without ever re-checking allowedServers again once the group-level connection is authorized. A key explicitly scoped to one specific server therefore also grants full access to every other server that happens to share a group with it, including servers the key was never authorized for. This issue has been patched in version 1.0.31.

The record
Technical detail
CVSS v3.1
8.1 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00426 · 35.8th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-08-31T22:17Z
References (4)
EPSS history
Timeline
  • 02 SEP 03:39Z
    EPSS moved — → 0%
    epss
  • 31 AUG 17:55Z
    MCPHub: Server-scoped bearer key gains access to an entire group via partial (any-overlap) server matching
    cvelistv5