Vulnerability · Published Nov 3, 2026 · Assigned by GitHub_M
CVE-2026-76894CKAN MCP Server: DataStore Table UI resource does not validate postMessage origin (in) and posts to targetOrigin "*" (out)
Low 3.1
In plain English
A low-severity insufficient verification of data authenticity in ckan-mcp-server from ondata. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @aborruso/ckan-mcp-server | 0.4.112 | GHSA-vqff-r82h-9crc |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ondata | ckan-mcp-server | < 0.4.112 |
Weakness: CWE-345, CWE-940 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N