CVE-2026-76894
Dashboard / Vulnerabilities / CVE-2026-76894
Summary: CKAN MCP Server: DataStore Table UI resource does not validate postMessage origin (in) and posts to targetOrigin "*" (out)
Details: 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.
References: https://github.com/ondata/ckan-mcp-server/releases/tag/v0.4.112, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76894.json, https://github.com/ondata/ckan-mcp-server/security/advisories/GHSA-vqff-r82h-9crc, https://nvd.nist.gov/vuln/detail/CVE-2026-76894, https://github.com/ondata/ckan-mcp-server/commit/3b827af72b228d42aa7b0d7dac5347d16af3f4e5
Affected packages
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