CVE-2026-67430 (GCVE-0-2026-67430)
Vulnerability from cvelistv5
Published
2026-07-29 19:10
Modified
2026-07-30 15:19
Severity ?
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Summary
MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem does not expire sessions by default, so repeated initialize requests retain unbounded ServerSession objects and can exhaust process memory. This issue is fixed in version 0.23.0.
References
Impacted products
Vendor Product Version
modelcontextprotocol ruby-sdk Version: < 0.23.0
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