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    2 vulnerabilities by cbcoutinho

    CVE-2026-55640 (GCVE-0-2026-55640)

    Vulnerability from nvd – Published: 2026-08-25 16:03 – Updated: 2026-08-25 19:20
    VLAI
    Title
    Nextcloud MCP Server: Unauthenticated `POST /webhooks/nextcloud` allows arbitrary vector data deletion when `WEBHOOK_SECRET` is unset ( default )
    Summary
    Nextcloud MCP Server is a production-ready MCP server that connects AI assistants to a Nextcloud instance. Prior to 0.117.2, the POST /webhooks/nextcloud endpoint in nextcloud_mcp_server/vector/webhook_receiver.py has no authentication by default because WEBHOOK_SECRET defaults to None and startup validation does not require it. When WEBHOOK_SECRET is unset, handle_nextcloud_webhook() accepts unauthenticated requests. The payload["user"]["uid"] field parsed in nextcloud_mcp_server/vector/webhook_parser.py is attacker-controlled and is used without an authenticated-session cross-check for Qdrant operations, allowing a network attacker to delete or trigger re-indexing of vector embeddings for any user and to destroy the semantic search index by sending forged deletion events. This issue is fixed in version 0.117.2.
    Severity
    9.1 (Critical)
    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
    SSVC
    Exploitation: none Automatable: yes Technical Impact: partial
    CISA Coordinator · CISA-ADP (v2.0.3)
    Decision recorded 2026-08-25 18:38 UTC
    CWE
    • CWE-306 - Missing Authentication for Critical Function
    Assigner
    References
    Impacted products
    Show details on NVD website
    To clipboard 

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    CVE-2026-55640 (GCVE-0-2026-55640)

    Vulnerability from cvelistv5 – Published: 2026-08-25 16:03 – Updated: 2026-08-25 19:20
    VLAI
    Title
    Nextcloud MCP Server: Unauthenticated `POST /webhooks/nextcloud` allows arbitrary vector data deletion when `WEBHOOK_SECRET` is unset ( default )
    Summary
    Nextcloud MCP Server is a production-ready MCP server that connects AI assistants to a Nextcloud instance. Prior to 0.117.2, the POST /webhooks/nextcloud endpoint in nextcloud_mcp_server/vector/webhook_receiver.py has no authentication by default because WEBHOOK_SECRET defaults to None and startup validation does not require it. When WEBHOOK_SECRET is unset, handle_nextcloud_webhook() accepts unauthenticated requests. The payload["user"]["uid"] field parsed in nextcloud_mcp_server/vector/webhook_parser.py is attacker-controlled and is used without an authenticated-session cross-check for Qdrant operations, allowing a network attacker to delete or trigger re-indexing of vector embeddings for any user and to destroy the semantic search index by sending forged deletion events. This issue is fixed in version 0.117.2.
    Severity
    9.1 (Critical)
    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
    SSVC
    Exploitation: none Automatable: yes Technical Impact: partial
    CISA Coordinator · CISA-ADP (v2.0.3)
    Decision recorded 2026-08-25 18:38 UTC
    CWE
    • CWE-306 - Missing Authentication for Critical Function
    Assigner
    References
    Impacted products
    Show details on NVD website
    To clipboard 

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