CVE-2026-76894
CKAN MCP Server: DataStore Table UI resource does not validate postMessage origin (in) and posts to targetOrigin "*" (out)
- 3.1LowCVSS base score
- 0.20%Exploitation in 30 daysEPSS · top 91% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/ondata/ckan-mcp-server/security/advisories/GHSA-vqff-r82h-9crc (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
- 6 days later
· 6 days later
Public exploit appeared
A proof of concept or exploit was published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Low3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N |
| NVDNVD · Received | 3.1 | Low3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.20% · top 91% of all CVEs (9 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.1.
Affected products
- affected < 0.4.112
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@aborruso/ckan-mcp-serverGHSA-vqff-r82h-9crc (opens in a new tab)
References
3
- https://github.com/ondata/ckan-mcp-server/security/advisories/GHSA-vqff-r82h-9crc (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/ondata/ckan-mcp-server/commit/3b827af72b228d42aa7b0d7dac5347d16af3f4e5 (opens in a new tab)x_refsource_MISC
- https://github.com/ondata/ckan-mcp-server/releases/tag/v0.4.112 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-116490 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-vqff-r82h-9crc (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-76894)Record last updated .