Access Control: Amazon Web Services

ABSTRACT

如果在使用用戶控制的項名稱且沒有適當 access control 的情形下訪問 SimpleDB 數據庫，則會允許攻擊者查看未經授權的記錄。

EXPLANATION

Database access control 錯誤在以下情況下發生：

1. 數據從一個不可信賴的數據源進入程序。

2. 此數據被用于指定 SimpleDB 訪問調用中的項目名。

例 1：以下代碼對在事務日期后命名的清單數據庫進行操作。此程序首先驗證客戶，然后使客戶能夠從以前的清單列表中選擇。


...
String selectedInvoice = request.getParameter("invoiceDate");
...
AmazonSimpleDBClient sdbc = new AmazonSimpleDBClient(appAWSCredentials);
GetAttributesResult sdbResult = sdbc.getAttributes(new GetAttributesRequest("invoices", selectedInvoice));
...

雖然例 1 中的代碼生成了一個當前用戶的清單列表，但是攻擊者可以繞過這個代碼行為，從而獲取所需的任何清單。因為此例中的代碼沒有執行檢查，確保用戶有權訪問需要的清單，所以代碼會顯示所有清單，即使這些清單并不屬于當前用戶。

REFERENCES

[1] Standards Mapping - OWASP Top 10 2004 - (OWASP 2004) A2 Broken Access Control

[2] Standards Mapping - OWASP Top 10 2007 - (OWASP 2007) A4 Insecure Direct Object Reference

[3] Standards Mapping - OWASP Top 10 2010 - (OWASP 2010) A4 Insecure Direct Object References

[4] Standards Mapping - FIPS200 - (FISMA) AC

[5] Standards Mapping - Security Technical Implementation Guide Version 3 - (STIG 3) APP3510 CAT I

[6] Standards Mapping - Security Technical Implementation Guide Version 3.4 - (STIG 3.4) APP3510 CAT I

[7] Standards Mapping - Common Weakness Enumeration - (CWE) CWE ID 566

[8] Standards Mapping - Web Application Security Consortium 24 + 2 - (WASC 24 + 2) Insufficient Authorization

[9] Standards Mapping - SANS Top 25 2011 - (SANS Top 25 2011) Porous Defenses - CWE ID 863

[10] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 - (PCI 1.1) Requirement 6.5.2

[11] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 - (PCI 1.2) Requirement 6.5.4

[12] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 - (PCI 2.0) Requirement 6.5.8

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