Privilege Escalation in Echo Go with Cockroachdb

Privilege escalation in an Echo Go service that uses CockroachDB typically arises when authorization checks are incomplete and database permissions are overly permissive. In a multi-tenant application, BOLA/IDOR and BFLA (Broken Function Level Authorization) can converge when route parameters such as userID are bound directly to SQL queries without validating that the requesting actor owns or is permitted to act on the targeted resource. If the Go handler uses a shared database user or an ORM with auto-preparing statements that bypass row-level security, an attacker can modify the ID in the URL to access or modify another user’s data, effectively escalating their privilege within the application logic.

When CockroachDB is the backend, specific misconfigurations can amplify the risk. For example, using the built-in postgres user with powerful roles or granting SELECT on sensitive system tables can expose metadata that aids an attacker. If the Echo Go application does not enforce tenant isolation at the query layer—such as missing tenant_id predicates in WHERE clauses—an attacker who can manipulate identifiers may read or update rows belonging to other tenants. Additionally, if the application dynamically constructs SQL with string concatenation instead of using prepared statements or parameterized queries, it may open indirect paths for privilege escalation through injection that changes the operation’s intent (e.g., modifying an UPDATE to affect other users).

The combination of Echo Go’s flexible routing and CockroachDB’s SQL semantics means that developers must explicitly model tenant boundaries and role privileges. Without explicit checks, a handler that fetches a user profile by ID can be tricked into fetching and editing another profile if the handler does not verify ownership. CockroachDB’s serializable isolation and unique secondary index features do not automatically protect against application-layer authorization flaws; they must be leveraged intentionally, for example by encoding tenant_id into primary keys or using secondary indexes that enforce tenant scoping. If the application relies on the database for access control by using row-level security but the Echo Go handlers do not pass the correct session context (such as tenant ID or role), the controls can be bypassed, leading to unauthorized operations and privilege escalation.

To remediate privilege escalation in Echo Go with CockroachDB, enforce tenant isolation and least-privilege database access in both application code and database configuration. Use parameterized queries, validate ownership on every request, and ensure that SQL statements include tenant context. Below are concrete code examples that demonstrate these practices.

First, define a tenant-aware query using placeholders and explicit tenant_id binding:

// tenant-aware handler in Echo Go
func GetProfile(c echo.Context) error {
    userID := c.Param("user_id")
    tenantID := c.Get("tenant_id").(string)
    var profile Profile
    // Use parameterized query to prevent injection and enforce tenant scope
    err := db.QueryRow(context.Background(),
        `SELECT id, name, email FROM profiles WHERE id = $1 AND tenant_id = $2`, userID, tenantID).Scan(&profile.ID, &profile.Name, &profile.Email)
    if err != nil {
        return echo.NewHTTPError(http.StatusNotFound, "profile not found")
    }
    return c.JSON(http.StatusOK, profile)
}

Second, apply the principle of least privilege to the CockroachDB role used by the application. Avoid using the default root or broad roles; instead, create a role with only necessary permissions and explicitly grant it on specific schemas and tables:

-- CockroachDB SQL to create a least-privilege role
CREATE ROLE app_reader;
GRANT SELECT ON TABLE profiles TO app_reader;
GRANT SELECT ON TABLE tenants TO app_reader;
-- Ensure the role cannot escalate via other schemas
REVOKE ALL ON SCHEMA public FROM app_reader;

Third, enforce tenant scoping at the primary key design level by including tenant_id in composite keys, which leverages CockroachDB’s indexing to prevent cross-tenant reads:

-- Table definition with tenant_id in primary key
CREATE TABLE profiles (
    tenant_id STRING NOT NULL,
    user_id   STRING NOT NULL,
    name      STRING,
    email     STRING,
    CONSTRAINT profiles_pkey PRIMARY KEY (tenant_id, user_id)
);
-- Create an index that supports tenant-specific queries
CREATE INDEX idx_profiles_tenant_user ON profiles (tenant_id, user_id);

Finally, in the Echo Go middleware, ensure the tenant context is validated before any database operation and that role checks align with the intended privilege boundaries:

// Middleware to enforce tenant context
tenantMiddleware := func(next echo.HandlerFunc) echo.HandlerFunc {
    return func(c echo.Context) error {
        tenantID, err := resolveTenant(c.Request())
        if err != nil {
            return echo.NewHTTPError(http.StatusForbidden, "invalid tenant")
        }
        c.Set("tenant_id", tenantID)
        return next(c)
    }
}

By combining these application-level checks with CockroachDB’s role-based access controls and primary key design, you reduce the surface for privilege escalation and ensure that each operation is scoped to the correct tenant and permission set.