CVE-2026-73846: CKAN MCP Server: Cache-key canonicalization collision enables cache confusion / poisoning

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-14 · updated 2026-09-18
Weakness: CWE-345

Description

CKAN MCP Server is a tool for querying CKAN open data portals. Prior to 0.4.112, canonicalizeParams in src/utils/cache.ts serializes request parameters with unescaped ampersand, equals-sign, and vertical-bar delimiters, allowing different logical parameter sets used by buildCacheKey to collide and an attacker to prime a shared cache with a response for a victim's distinct query. This issue is fixed in version 0.4.112.

Affected products

ondata ckan-mcp-server: before 0.4.112

References

https://github.com/ondata/ckan-mcp-server/commit/8e1522f9bbfa1f3b21550f17887f60f133e24151
https://github.com/ondata/ckan-mcp-server/releases/tag/v0.4.112
https://github.com/ondata/ckan-mcp-server/security/advisories/GHSA-78x9-fhhx-v2g6
https://github.com/ondata/ckan-mcp-server/security/advisories/GHSA-78x9-fhhx-v2g6

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