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2 vulnerabilities found for ruby-sdk by modelcontextprotocol

CVE-2026-33946 (GCVE-0-2026-33946)

Vulnerability from nvd – Published: 2026-03-27 21:20 – Updated: 2026-03-30 18:42
VLAI?
Title
MCP Ruby SDK: Insufficient Session Binding Allows SSE Stream Hijacking via Session ID Replay
Summary
MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to version 0.9.2, the Ruby SDK's streamable_http_transport.rb implementation contains a session hijacking vulnerability. An attacker who obtains a valid session ID can completely hijack the victim's Server-Sent Events (SSE) stream and intercept all real-time data. Version 0.9.2 contains a patch.
Severity ?
8.2 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-384 - Session Fixation
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
Impacted products
Vendor Product Version
modelcontextprotocol ruby-sdk Affected: < 0.9.2
Create a notification for this product.
Show details on NVD website
To clipboard 

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CVE-2026-33946 (GCVE-0-2026-33946)

Vulnerability from cvelistv5 – Published: 2026-03-27 21:20 – Updated: 2026-03-30 18:42
VLAI?
Title
MCP Ruby SDK: Insufficient Session Binding Allows SSE Stream Hijacking via Session ID Replay
Summary
MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to version 0.9.2, the Ruby SDK's streamable_http_transport.rb implementation contains a session hijacking vulnerability. An attacker who obtains a valid session ID can completely hijack the victim's Server-Sent Events (SSE) stream and intercept all real-time data. Version 0.9.2 contains a patch.
Severity ?
8.2 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-384 - Session Fixation
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
Impacted products
Vendor Product Version
modelcontextprotocol ruby-sdk Affected: < 0.9.2
Create a notification for this product.
Show details on NVD website
To clipboard 

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