加密密鑰會削弱系統安全性，并且無法輕易修正出現的安全問題。
采用硬編碼處理加密密鑰絕非一個好方法。這不僅是因為采用硬編碼方式處理的加密密鑰能被項目的所有開發人員看到，而且還會大大增加解決問題的難度。一旦代碼被使用，除非對軟件進行修補，否則加密密鑰將再也不能更改。如果帳戶中的加密密鑰保護減弱，系統所有者將被迫在安全性和可行性之間做出選擇。
例 1：下列代碼使用了硬編碼加密密鑰：
...
NSString encyrptionKey = "lakdsljkalkjlksdfkl";
...
[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, CWE ID 798
[7] Standards Mapping - FIPS200 - (FISMA) IA
[8] iOS On-Disk Encryption Apple
[9] Standards Mapping - SANS Top 25 2009 - (SANS 2009) Porous Defenses - CWE ID 259
[10] Standards Mapping - SANS Top 25 2010 - (SANS 2010) Porous Defenses - CWE ID 798
[11] Standards Mapping - SANS Top 25 2011 - (SANS Top 25 2011) Porous Defenses - CWE ID 798
[12] 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
[13] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 - (PCI 2.0) Requirement 3.4, Requirement 6.5.3, Requirement 8.4
[14] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 - (PCI 1.1) Requirement 3.4, Requirement 6.5.8, Requirement 8.4