CVE-2026-76894

CKAN MCP Server: DataStore Table UI resource does not validate postMessage origin (in) and posts to targetOrigin "*" (out)

Published Nov 3, 2026 CVSS 3.1 · 3.1 Low EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-vqff-r82h-9crc ckan-mcp-server: DataStore Table UI resource does not validate postMessage origin (in) and posts to targetOrigin "*" (out)
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Ondata
Ondata ckan-mcp-server
Vendors & Products Ondata
Ondata ckan-mcp-server
Type Values Removed Values Added
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.
Title CKAN MCP Server: DataStore Table UI resource does not validate postMessage origin (in) and posts to targetOrigin "*" (out)
Weaknesses CWE-345
CWE-940
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Nov 9, 2026, 3:48 PM
Reserved
Aug 19, 2026, 10:43 PM
Status
Deferred
Published
Nov 3, 2026, 9:17 PM
Modified
Nov 12, 2026, 8:07 PM