CVE-2026-63119 (GCVE-0-2026-63119)
Vulnerability from cvelistv5
Published
2026-07-29 19:12
Modified
2026-07-29 19:28
Severity ?
6.2 (Medium) - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • 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::StdioTransport and MCP::Client::Stdio in the mcp gem use IO#gets without a byte limit, allowing a peer that sends data without a newline to 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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