CVE-2026-76894

What it is

CKAN MCP Server is a tool for querying CKAN open data portals. Prior to 0.4.112, the DataStore table UI in src/resources/datastore-table-ui.ts accepts window message events without validating event.origin and sends JSON-RPC messages through postMessage with a wildcard target origin. A frame that can reach the embedded document can inject fabricated fields or records, spoof pending ui/initialize responses, disrupt the MCP UI handshake, or receive outbound messages when the resource is embedded by an untrusted parent. Values are HTML escaped, so the demonstrated content injection is display spoofing rather than script execution, and exploitability depends on the host embedding model. This issue is fixed in version 0.4.112.

At a glance

Exploitability

Can be exploited over the network without logging in, but needs a user to act. Limited direct impact.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-11-03 21:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-11-03 21:17 UTC Last updatedMost recent change to the record

Details

Published

2026-11-03 21:17 UTC

Last modified

2026-11-03 21:17 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-345

Record status

Received

Attack profile CVSS 3.1 · 3.1

Attack vector

Network

Complexity

High

Privileges needed

None

User interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None