Null 加密密鑰會削弱安全性。
最好不要為加密密鑰變量指定 null,因為攻擊者可以借此泄露敏感信息和加密的信息。
例如:以下代碼可將加密密鑰變量初始化為 null。
...
$encrption_key = NULL;
$filter = new Zend_Filter_Encrypt($encrption_key);
$filter->setVector('myIV');
$encrypted = $filter->filter('text_to_be_encrypted');
print $encrypted;
...
[1] Standards Mapping - OWASP Top 10 2010 - (OWASP 2010) A7 Insecure Cryptographic Storage
[2] Standards Mapping - OWASP Top 10 2007 - (OWASP 2007) A8 Insecure Cryptographic Storage
[3] Standards Mapping - OWASP Top 10 2004 - (OWASP 2004) A8 Insecure Storage
[4] Standards Mapping - Security Technical Implementation Guide Version 3 - (STIG 3) APP3210.1 CAT II, APP3340 CAT I, APP3350 CAT I
[5] Standards Mapping - Security Technical Implementation Guide Version 3.4 - (STIG 3.4) APP3210.1 CAT II, APP3340 CAT I, APP3350 CAT I
[6] Standards Mapping - Common Weakness Enumeration - (CWE) CWE ID 259
[7] Standards Mapping - FIPS200 - (FISMA) IA
[8] Standards Mapping - SANS Top 25 2009 - (SANS 2009) Porous Defenses - CWE ID 259
[9] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 - (PCI 1.2) Requirement 3.4, Requirement 6.3.1.3, Requirement 6.5.8, Requirement 8.4
[10] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 - (PCI 2.0) Requirement 3.4, Requirement 6.5.3, Requirement 8.4
[11] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 - (PCI 1.1) Requirement 3.4, Requirement 6.5.8, Requirement 8.4