CyberSecBulletin
CVE-2026-79750NVD status: Awaiting Analysis

mcphub: Authorization Bypass Through User-Controlled Key

Published Updated By the CyberSecBulletin desk

CVE-2026-79750 is a high-severity authorization bypass through user-controlled key vulnerability in mcphub from Samanhappy, with a CVSS 3.1 base score of 7.7 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected mcphub versions: < 1.0.30. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of mcphub you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Samanhappymcphub< 1.0.30Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N. Scored by CNA (github.com).

Official description

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 1.0.30, MCPHub scopes non-admin users to servers they own (list views and config edits enforce ownership), but the tool-execution API does not. Any authenticated non-admin user can invoke tools on MCP servers owned by other users — servers they cannot even see in GET /api/servers. Because connected MCP servers carry real capability (filesystem, HTTP fetch, cloud APIs with the owner's keys), this is cross-tenant compromise: demonstrated arbitrary host file read (/etc/passwd, another user's secrets) and SSRF. This issue has been patched in version 1.0.30.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Authorization Bypass Through User-Controlled Key

The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

How developers prevent this class of flaw

  • For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
  • Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
  • Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.

More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in mcphub

All mcphub vulnerabilities

Recent Authorization Bypass Through User-Controlled Key vulnerabilities

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