Cache poisoning via delimiter-ambiguous parameter serialization
Published Aug 14, 2026 · Updated Aug 14, 2026
Cache poisoning in onData CKAN MCP Server before 0.4.111 allows remote attackers to serve incorrect results through a shared cache. canonicalizeParams joins sorted parameters using unescaped ampersand and equals-sign delimiters, while buildCacheKey adds unescaped vertical bars, so distinct requests hash to one key. Exploitation requires a shared, enabled cache and attacker priming before the victim request; the victim receives attacker-selected public data from the same portal.
Summary
What happened
Cache poisoning in onData CKAN MCP Server before 0.4.111 allows remote attackers to serve incorrect results through a shared cache. canonicalizeParams joins sorted parameters using unescaped ampersand and equals-sign delimiters, while buildCacheKey adds unescaped vertical bars, so distinct requests hash to one key. Exploitation requires a shared, enabled cache and attacker priming before the victim request; the victim receives attacker-selected public data from the same portal.
The record
- CVE
- CVE-2026-73846
- Published
- Aug 14, 2026
- Updated
- Aug 14, 2026
- Vendor
- onData
- Product
- CKAN MCP Server
- Classifications
- CWE-345, CWE-436, T1565.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 14, 2026CVE publishedPublication date reported by the CVE source.
- Aug 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 0.4.112
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- cache-collision-poc.mjsproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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