Credential Stuffing in Cockroachdb

Credential stuffing attacks targeting Cockroachdb applications exploit the database's distributed architecture and SQL interface. Attackers use breached username/password combinations from other breaches to attempt authentication against Cockroachdb-backed services. The distributed nature of Cockroachdb means authentication attempts can hit different nodes, making rate limiting more challenging without proper coordination.

In Cockroachdb, credential stuffing typically manifests through repeated failed login attempts that generate audit logs and connection errors. The crdb_internal.node_connectivity system table shows connection patterns that may indicate automated attacks. Attackers often target the crdb_internal schema to gather information about the cluster's topology before launching credential stuffing campaigns.

Common attack patterns include:

• Brute-force authentication attempts against application endpoints that connect to Cockroachdb
• Exploitation of default credentials on Cockroachdb admin interfaces
• Targeting of connection pools that maintain persistent connections to the database
• Attempts to access Cockroachdb's built-in SQL shell through exposed endpoints
• Exploitation of Cockroachdb's role-based access control (RBAC) to escalate privileges

Applications using Cockroachdb often implement connection pooling with libraries like pgxpool or lib/pq. These pools can mask credential stuffing attempts if not properly monitored. A typical vulnerable pattern looks like:

// Vulnerable: No rate limiting or credential monitoring
pool, _ := pgxpool.Connect(context.Background(), connStr)
for i := 0; i < 1000; i++ {
    pool.Begin(context.Background()) // Repeated auth attempts
}

The distributed transaction system in Cockroachdb can also be abused. Attackers may use credential stuffing to gain access, then execute distributed transactions across multiple nodes to exfiltrate data without triggering single-node security alerts.

Detecting credential stuffing in Cockroachdb environments requires monitoring both the database and application layers. Cockroachdb provides several system tables and audit mechanisms specifically useful for this purpose.

Key detection methods:

• Audit Logs: Enable Cockroachdb's enterprise audit logs to track all authentication attempts. The ALTER TABLE ... EXPERIMENTAL AUDIT statement captures DDL and DML operations with user context.
• System Tables: Query crdb_internal.node_connectivity and crdb_internal.node_runtime_info to identify unusual connection patterns from specific IPs or ranges.
• Statement Statistics: Use crdb_internal.statement_statistics to find repeated failed authentication queries with similar patterns.
• Network Monitoring: Monitor for sudden spikes in connection attempts using Cockroachdb's crdb_internal.node_network_info.

Sample detection query for suspicious authentication patterns:

SELECT 
    user_name, 
    client_address, 
    COUNT(*) as auth_attempts,
    SUM(CASE WHEN success THEN 1 ELSE 0 END) as successes,
    SUM(CASE WHEN NOT success THEN 1 ELSE 0 END) as failures,
    MAX(failed_attempt_time) - MIN(failed_attempt_time) as duration

middleBrick's black-box scanning approach is particularly effective for detecting credential stuffing vulnerabilities in Cockroachdb applications. The scanner tests for:

• Missing rate limiting on authentication endpoints
• Default credential exposure
• Insecure session management
• Insufficient authentication logging
• Exposed admin interfaces

The scanner executes 12 parallel security checks in approximately 5-15 seconds without requiring credentials or access to the database internals. For Cockroachdb applications, middleBrick specifically tests for authentication bypass patterns and rate limiting weaknesses that could enable credential stuffing attacks.

Remediating credential stuffing vulnerabilities in Cockroachdb environments requires a layered approach combining database configuration, application-level controls, and monitoring.

Database Configuration

Implement connection limits and authentication controls at the database level:

-- Create a role with limited connection attempts
CREATE ROLE limited_connections WITH PASSWORD 'strong_password' CONNECTION LIMIT 5;

Application-Level Controls

Implement rate limiting and credential monitoring in your application code:

// Secure Cockroachdb connection with rate limiting
type RateLimiter struct {
    attempts map[string]int
    lastAttempt map[string]time.Time
    mu sync.Mutex
}

func (rl *RateLimiter) Allow(ip string) bool {
    rl.mu.Lock()
    defer rl.mu.Unlock()
    
    now := time.Now()
    if last, exists := rl.lastAttempt[ip]; exists {
        if now.Sub(last) < time.Minute {
            if rl.attempts[ip] > 5 {
                return false // Rate limited
            }
            rl.attempts[ip]++
        } else {
            rl.attempts[ip] = 1
            rl.lastAttempt[ip] = now
        }
    } else {
        rl.attempts[ip] = 1
        rl.lastAttempt[ip] = now
    }
    return true
}

func AuthenticateUser(ctx context.Context, username, password, ip string) error {
    limiter := RateLimiter{}
    if !limiter.Allow(ip) {
        return errors.New("rate limit exceeded")
    }
    
    conn, err := pgx.Connect(ctx, connStr)
    if err != nil {
        return err
    }
    defer conn.Close(ctx)
    
    var count int
    err = conn.QueryRow(ctx, 
        "SELECT COUNT(*) FROM users WHERE username=$1 AND password=$2",
        username, password).Scan(&count)
    
    if err != nil || count == 0 {
        // Log failed attempt to Cockroachdb audit table
        _, err := conn.Exec(ctx, 
            "INSERT INTO auth_attempts (username, ip, success, timestamp) VALUES ($1, $2, $3, $4)",
            username, ip, false, time.Now())
        return errors.New("invalid credentials")
    }
    return nil
}

Monitoring and Alerting

Set up continuous monitoring with middleBrick's Pro plan features:

• Schedule scans to run every 5 minutes on authentication endpoints
• Configure alerts when authentication failure rates exceed thresholds
• Use the GitHub Action to fail builds if security scores drop below acceptable levels
• Integrate with Slack/Teams for real-time notifications of credential stuffing attempts

Additional Security Measures

Implement multi-factor authentication (MFA) for all administrative access to Cockroachdb clusters. Use Cockroachdb's built-in role-based access control to limit privileges based on the principle of least privilege. Enable enterprise features like audit logging and configure appropriate retention policies for security logs.

For applications using Cockroachdb's distributed transactions, ensure that authentication tokens are validated before allowing transaction execution across nodes. This prevents credential stuffing attackers from exploiting the distributed nature of the database to bypass single-node security controls.