OSSEC and/or Journalist alert private key compromised partially mitigated

THREAT70 · Partially mitigated: Some controls are in place, but the risk is still too high. · Defined in catalog.py:1233

Risk: Low impact × Low likelihood = 2 low
After mitigations: Low impact × Low likelihood = 2 low (unchanged)

How statuses and scores work

Can read alerts in combination with corresponding SMTP relay compromise

Threat actors: Nation State / Law Enforcement Large Corporation Hacker

Mitigations

Mitigation	Status
OSSEC logs do not contain sensitive information. MITIG148	implemented

Possible further mitigations

Use Signal for OSSEC alerts MITIG237 proposed

Residual risk

An adversary would be able to fingerprint a SecureDrop server sending.

Where it applies

Applies to 2 components in 2 scenarios.

Journalist Corporate Workstation News Organization
Postfix Monitoring Server

Monitoring & alerting · Postfix

digraph tm {
    graph [
        fontname = Arial;
        fontsize = 14;
    ]
    node [
        fontname = Arial;
        fontsize = 14;
    ]
    edge [
        fontname = Arial;
        fontsize = 12;
    ]
    nodesep = 1;

    subgraph cluster_boundary_Application_Server {
        graph [
            fontsize = 10;
            fontcolor = black;
            style = dashed;
            color = firebrick2;
            label = <<i>Application Server</i>>;
        ]

        component_OSSEC_client_Application_Server [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "OSSEC client";
            URL = "component_OSSEC_client.html";
            tooltip = "OSSEC client";
            margin = 0.02;
        ]

    }

    subgraph cluster_boundary_External_Services {
        graph [
            fontsize = 10;
            fontcolor = black;
            style = dashed;
            color = firebrick2;
            label = <<i>External Services</i>>;
        ]

        component_SMTP_relay_External_Services [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "SMTP relay";
            URL = "component_SMTP_relay.html";
            tooltip = "SMTP relay";
            margin = 0.02;
        ]

    }

    subgraph cluster_boundary_Monitoring_Server {
        graph [
            fontsize = 10;
            fontcolor = black;
            style = dashed;
            color = firebrick2;
            label = <<i>Monitoring Server</i>>;
        ]

        component_OSSEC_server_Monitoring_Server [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "OSSEC server";
            URL = "component_OSSEC_server.html";
            tooltip = "OSSEC server";
            margin = 0.02;
        ]

        component_Postfix_Monitoring_Server [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "Postfix";
            URL = "component_Postfix.html";
            tooltip = "Postfix";
            margin = 0.02;

            style = "filled";

            fillcolor = "#c0392b";

            fontcolor = "white";

            class = "highlighted";
        ]

    }

    actor_Administrator_ [
        shape = square;
        color = black;
        fontcolor = black;
        label = "Administrator";
        URL = "component_Administrator.html";
        tooltip = "Administrator";
        margin = 0.02;
    ]

    component_OSSEC_client_Application_Server -> component_OSSEC_server_Monitoring_Server [        color = black;        fontcolor = black;        dir = forward;        label = "1. Ship events";    ]
    component_OSSEC_server_Monitoring_Server -> component_Postfix_Monitoring_Server [        color = black;        fontcolor = black;        dir = forward;        label = "2. Raise alert";    ]
    component_Postfix_Monitoring_Server -> component_SMTP_relay_External_Services [        color = black;        fontcolor = black;        dir = forward;        label = "3. Relay mail";    ]
    component_SMTP_relay_External_Services -> actor_Administrator_ [        color = black;        fontcolor = black;        dir = forward;        label = "4. Deliver to admin";    ]
}

Corporate and legal zone · Journalist Corporate Workstation

digraph tm {
    graph [
        fontname = Arial;
        fontsize = 14;
    ]
    node [
        fontname = Arial;
        fontsize = 14;
    ]
    edge [
        fontname = Arial;
        fontsize = 12;
    ]
    nodesep = 1;

    subgraph cluster_boundary_External_Services {
        graph [
            fontsize = 10;
            fontcolor = black;
            style = dashed;
            color = firebrick2;
            label = <<i>External Services</i>>;
        ]

        component_SMTP_relay_External_Services [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "SMTP relay";
            URL = "component_SMTP_relay.html";
            tooltip = "SMTP relay";
            margin = 0.02;
        ]

    }

    subgraph cluster_boundary_News_Organization {
        graph [
            fontsize = 10;
            fontcolor = black;
            style = dashed;
            color = firebrick2;
            label = <<i>News Organization</i>>;
        ]

        component_Journalist_Corporate_Workstation_News_Organization [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "Journalist\nCorporate\nWorkstation";
            URL = "component_Journalist_Corporate_Workstation.html";
            tooltip = "Journalist Corporate Workstation";
            margin = 0.02;

            style = "filled";

            fillcolor = "#c0392b";

            fontcolor = "white";

            class = "highlighted";
        ]

        component_News_Organization___Legal_News_Organization [
            shape = circle;
            color = black;
            fontcolor = black;
            label = "News\nOrganization /\nLegal";
            URL = "component_News_Organization___Legal.html";
            tooltip = "News Organization / Legal";
            margin = 0.02;
        ]

    }

    actor_Journalist_ [
        shape = square;
        color = black;
        fontcolor = black;
        label = "Journalist";
        URL = "component_Journalist.html";
        tooltip = "Journalist";
        margin = 0.02;
    ]

    actor_Journalist_ -> component_Journalist_Corporate_Workstation_News_Organization [        color = black;        fontcolor = black;        dir = forward;        label = "1. Journalist uses\ncorporate device";    ]
    component_SMTP_relay_External_Services -> component_Journalist_Corporate_Workstation_News_Organization [        color = black;        fontcolor = black;        dir = forward;        label = "2. Alerts to\ncorporate mail";    ]
    component_Journalist_Corporate_Workstation_News_Organization -> component_News_Organization___Legal_News_Organization [        color = black;        fontcolor = black;        dir = forward;        label = "3. Organizational /\nlegal exposure";    ]
}

Notes

Existing mitigations: OSSEC alerts are scrubbed for sensitive contents (application data, server IPs) (MITIG148). Further mitigations: Move Ossec alerts to Signal (MITIG237). Automated test for mitigation: No.

How this threat is matched

Listed for these components. A boundary covers every component inside it.