Cross-Site Request Forgery

ABSTRACT

表單發布必須包含用戶特有的機密，防止攻擊者發出未經授權的請求。

EXPLANATION

跨站點偽裝請求 (CSRF) 漏洞會在以下情況下發生：
1. Web 應用程序使用會話 cookie。

2. 應用程序未驗證請求是否經過用戶同意便處理 HTTP 請求。



如果該請求未包含證明其來源的 nonce，則處理該請求的代碼將易受到 CSRF 攻擊（除非它并未更改應用程序的狀態）。這意味著使用會話 cookie 的 Web 應用程序必須采取特殊的預防措施，確保攻擊者無法誘騙用戶提交偽請求。假設有一個 Web 應用程序，它允許管理員通過提交此表單來創建新帳戶：

<form method="POST" action="/new_user" >
Name of new user:<input type="text" name="username">
Password for new user:<input type="password" name="user_passwd">
<input type="submit" name="action" value="Create User">
</form>

<form method="POST" action="http://www.example.com/new_user">
<input type="hidden" name="username" value="hacker">
<input type="hidden" name="user_passwd" value="hacked">
</form>
<script>
document.usr_form.submit();
</script>

REFERENCES

[1] OWASP 2007 OWASP Top 10

[2] Standards Mapping - OWASP Top 10 2007 - (OWASP 2007) A5 Cross Site Request Forgery (CSRF)

[3] Standards Mapping - OWASP Top 10 2010 - (OWASP 2010) A5 Cross-Site Request Forgery (CSRF)

[4] Standards Mapping - Security Technical Implementation Guide Version 3 - (STIG 3) APP3585 CAT II

[5] Standards Mapping - Security Technical Implementation Guide Version 3.4 - (STIG 3.4) APP3585 CAT II

[6] Standards Mapping - Web Application Security Consortium 24 + 2 - (WASC 24 + 2) Cross-Site Request Forgery

[7] Standards Mapping - Common Weakness Enumeration - (CWE) CWE ID 352

[8] A. Klein Divide and Conquer:HTTP Response Splitting, Web Cache Poisoning Attacks, and Related Topics

[9] Standards Mapping - SANS Top 25 2009 - (SANS 2009) Insecure Interaction - CWE ID 352

[10] Standards Mapping - SANS Top 25 2010 - (SANS 2010) Insecure Interaction - CWE ID 352

[11] Standards Mapping - SANS Top 25 2011 - (SANS Top 25 2011) Insecure Interaction - CWE ID 352

[12] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 - (PCI 1.2) Requirement 6.5.5

[13] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 - (PCI 2.0) Requirement 6.5.9