CVE-2026-76894
Published:October 16, 2026
Updated:October 18, 2026
The MCP Apps UI resource (an interactive DataStore table rendered in the host's webview/iframe) communicates with its parent via "postMessage". Its inbound "message" listener performs no "event.origin" validation, and its outbound messages are sent with target origin "'*'". Any window/frame able to reach the document can inject data into the table and interfere with the MCP UI handshake, and the UI's own JSON-RPC messages are broadcast without an origin restriction.
Affected Packages
@aborruso/ckan-mcp-server (NPM):
Affected version(s) >=0.3.1 <0.4.112Fix Suggestion:
Update to version 0.4.112Related Resources (2)
Do you need more information?
Contact UsCVSS v4
Base Score:
2.3
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
PASSIVE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
3.1
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE