Cross Site Request Forgery in Echo Go

Cross Site Request Forgery (CSRF) in Echo Go occurs when an attacker tricks a user's browser into making unauthorized requests to your Echo Go application. This is particularly dangerous in Echo Go because its middleware architecture and session handling can inadvertently expose endpoints to CSRF attacks if not properly configured.

The most common CSRF pattern in Echo Go applications involves state-changing operations like POST, PUT, DELETE, or PATCH requests that modify user data. Without proper CSRF protection, an attacker can craft a malicious HTML page that, when visited by an authenticated user, automatically submits a form or makes an AJAX request to your Echo Go API, causing unintended actions on behalf of the user.

Consider this vulnerable Echo Go endpoint:

func transferFunds(c echo.Context) error {
    userID := c.Get("user").(int64)
    amount := c.FormValue("amount")
    targetAccount := c.FormValue("target_account")
    
    // Process the transfer without CSRF protection
    return db.TransferFunds(userID, amount, targetAccount)
}

An attacker could create a malicious page with:

<form action="https://yourapp.com/api/transfer" method="POST" id="csrf-form" style="display:none">
    <input type="hidden" name="amount" value="1000">
    <input type="hidden" name="target_account" value="attacker_account">
</form>
<script>document.getElementById('csrf-form').submit();</script>

When an authenticated user visits this page, their browser automatically submits the form, transferring $1000 to the attacker's account without their knowledge. Echo Go's default behavior doesn't include CSRF protection, making this a critical vulnerability.

Another Echo Go-specific CSRF scenario involves WebSocket connections. If your Echo Go application uses WebSockets for real-time features and doesn't validate the origin of WebSocket connections, an attacker can establish a WebSocket connection from a malicious site and send commands to your Echo Go backend, bypassing traditional CSRF protections.

Detecting CSRF vulnerabilities in Echo Go applications requires both manual code review and automated scanning. middleBrick's API security scanner specifically tests for CSRF vulnerabilities by examining your Echo Go endpoints and attempting to identify unprotected state-changing operations.

middleBrick scans Echo Go applications by:

• Analyzing HTTP methods and endpoints to identify state-changing operations (POST, PUT, DELETE, PATCH)
• Checking for the absence of CSRF tokens or other anti-CSRF mechanisms
• Testing if endpoints accept cross-origin requests without proper validation
• Examining session management and authentication patterns specific to Echo Go
• Identifying Echo Go middleware configurations that might inadvertently enable CSRF

The scanner looks for Echo Go-specific patterns like:

// Vulnerable Echo Go pattern - no CSRF protection
func main() {
    e := echo.New()
    
    // Middleware that might be missing CSRF protection
    e.Use(middleware.Logger())
    e.Use(middleware.Recover())
    
    // State-changing endpoints without CSRF tokens
    e.POST("/api/users", createUser)
    e.PUT("/api/users/:id", updateUser)
    e.DELETE("/api/users/:id", deleteUser)
    
    e.Start(":1323")
}

middleBrick's CSRF detection also examines Echo Go's session handling. If your application uses Echo Go's default session middleware without additional CSRF protection, it may be vulnerable. The scanner tests whether session cookies are marked as SameSite or if they're accessible to cross-origin requests.

For WebSocket-based Echo Go applications, middleBrick tests WebSocket endpoint security by attempting to establish WebSocket connections from different origins and sending test commands to verify if the server validates connection origins and authenticates WebSocket messages.

The scanner provides specific findings for Echo Go applications, including:

• CSRF vulnerability in POST endpoint /api/transfer without anti-CSRF token
• Missing SameSite cookie attribute on session cookie
• Unprotected state-changing operation in PUT /api/users/:id
• WebSocket endpoint accepting connections from any origin

Each finding includes Echo Go-specific remediation guidance and severity assessment based on the potential impact of the CSRF vulnerability.

Securing Echo Go applications against CSRF requires implementing proper anti-CSRF mechanisms. The most effective approach is using CSRF tokens with Echo Go's middleware system. Here's how to implement CSRF protection in Echo Go:

package main

import (
    "github.com/labstack/echo/v4"
    "github.com/labstack/echo/v4/middleware"
)

func main() {
    e := echo.New()
    
    // Echo Go CSRF middleware configuration
    e.Use(middleware.CSRF())
    
    // Set custom CSRF token configuration
    e.Use(middleware.CSRFWithConfig(middleware.CSRFConfig{
        TokenLookup: "header:X-CSRF-Token",
        CookieName:  "csrf_token",
        CookiePath:  "/",
        CookieMaxAge: 86400, // 24 hours
        CookieSecure: true,  // Use HTTPS only
        CookieSameSite: http.SameSiteStrictMode,
    }))
    
    // Protected endpoints automatically validate CSRF tokens
    e.POST("/api/users", createUser)
    e.PUT("/api/users/:id", updateUser)
    e.DELETE("/api/users/:id", deleteUser)
    
    e.Start(":1323")
}

With this configuration, Echo Go automatically generates CSRF tokens, validates them on state-changing requests, and rejects requests without valid tokens. The middleware also sets the SameSite attribute on the CSRF cookie, preventing cross-site requests.

For applications that need more granular control, you can implement custom CSRF protection in Echo Go:

func csrfMiddleware(next echo.HandlerFunc) echo.HandlerFunc {
    return func(c echo.Context) error {
        // Generate or validate CSRF token
        if c.Request().Method == http.MethodPost || 
           c.Request().Method == http.MethodPut || 
           c.Request().Method == http.MethodDelete {
            
            token := c.Request().Header.Get("X-CSRF-Token")
            if token == "" || !validateCSRFToken(token) {
                return echo.NewHTTPError(http.StatusForbidden, "CSRF token missing or invalid")
            }
        }
        
        return next(c)
    }
}

func validateCSRFToken(token string) bool {
    // Implement your validation logic
    // Could check against session store, database, etc.
    return true // placeholder
}

For WebSocket connections in Echo Go, implement origin validation:

func wsHandler(c echo.Context) error {
    // Validate origin before accepting WebSocket connection
    origin := c.Request().Header.Get("Origin")
    if !isValidOrigin(origin) {
        return echo.NewHTTPError(http.StatusForbidden, "Invalid origin")
    }
    
    ws, err := upgrader.Upgrade(c.Response(), c.Request(), nil)
    if err != nil {
        return err
    }
    defer ws.Close()
    
    // Authenticate WebSocket messages
    for {
        _, message, err := ws.ReadMessage()
        if err != nil {
            break
        }
        
        // Validate message content and user permissions
        if !authenticateMessage(message) {
            ws.WriteMessage(websocket.TextMessage, []byte("Unauthorized"))
            continue
        }
        
        // Process valid message
    }
    
    return nil
}

Additionally, configure Echo Go to use SameSite cookies for session management:

func main() {
    e := echo.New()
    
    // Configure session middleware with SameSite
    e.Use(middleware.SessionsWithConfig(middleware.SessionsConfig{
        CookieName: "session",
        CookiePath: "/",
        CookieMaxAge: 86400,
        CookieSecure: true,
        CookieSameSite: http.SameSiteStrictMode,
    }))
    
    e.Start(":1323")
}

These Echo Go-specific implementations provide comprehensive CSRF protection by combining token validation, SameSite cookies, origin validation, and proper session management. middleBrick can verify these protections are correctly implemented through its security scanning.