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    2 vulnerabilities found for mcp_ruby_sdk by lfprojects

    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
    SSVC
    Exploitation: poc Automatable: yes Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-384 - Session Fixation
    • CWE-639 - Authorization Bypass Through User-Controlled Key
    Assigner
    References
    Impacted products
    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
    SSVC
    Exploitation: poc Automatable: yes Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-384 - Session Fixation
    • CWE-639 - Authorization Bypass Through User-Controlled Key
    Assigner
    References
    Impacted products
    Show details on NVD website
    To clipboard 

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