Interpretation Conflict Affecting github.com/modelcontextprotocol/go-sdk/internal/jsonrpc2 package, versions <1.3.1
Threat Intelligence
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Test your applications- Snyk IDSNYK-GOLANG-GITHUBCOMMODELCONTEXTPROTOCOLGOSDKINTERNALJSONRPC2-15369703
- published3 Mar 2026
- disclosed26 Feb 2026
- creditFrancesco Lacerenza
Introduced: 26 Feb 2026
CVE-2026-27896 (opens in a new tab)How to fix?
Upgrade github.com/modelcontextprotocol/go-sdk/internal/jsonrpc2 to version 1.3.1 or higher.
Overview
Affected versions of this package are vulnerable to Interpretation Conflict in the JSON-RPC and MCP protocol message parsing. An attacker can bypass intermediary inspection or cause cross-implementation inconsistencies by sending protocol messages with non-standard field casing or Unicode characters that are incorrectly matched to expected fields.