73 lines
2.5 KiB
Plaintext
73 lines
2.5 KiB
Plaintext
include::../description.adoc[]
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== Noncompliant Code Example
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----
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public class MyCbcClass {
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public String applyCBC(String strKey, String plainText) {
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byte[] bytesIV = "7cVgr5cbdCZVw5WY".getBytes("UTF-8");
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/* KEY + IV setting */
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IvParameterSpec iv = new IvParameterSpec(bytesIV);
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SecretKeySpec skeySpec = new SecretKeySpec(strKey.getBytes("UTF-8"), "AES");
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/* Ciphering */
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Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
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cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv); // Noncompliant: the IV is hard coded and thus not generated with a secure random generator
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byte[] encryptedBytes = cipher.doFinal(plainText.getBytes("UTF-8"));
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return DatatypeConverter.printBase64Binary(bytesIV)
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+ ";" + DatatypeConverter.printBase64Binary(encryptedBytes);
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}
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}
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----
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== Compliant Solution
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----
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public class MyCbcClass {
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SecureRandom random = new SecureRandom();
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public String applyCBC(String strKey, String plainText) {
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byte[] bytesIV = new byte[16];
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random.nextBytes(bytesIV);
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/* KEY + IV setting */
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IvParameterSpec iv = new IvParameterSpec(bytesIV);
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SecretKeySpec skeySpec = new SecretKeySpec(strKey.getBytes("UTF-8"), "AES");
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/* Ciphering */
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Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
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cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv); // Compliant
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byte[] encryptedBytes = cipher.doFinal(plainText.getBytes("UTF-8"));
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return DatatypeConverter.printBase64Binary(bytesIV)
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+ ";" + DatatypeConverter.printBase64Binary(encryptedBytes);
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}
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}
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----
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== See
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* https://owasp.org/Top10/A02_2021-Cryptographic_Failures/[OWASP Top 10 2021 Category A2] - Cryptographic Failures
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* https://www.owasp.org/index.php/Top_10-2017_A6-Security_Misconfiguration[OWASP Top 10 2017 Category A6] - Security Misconfiguration
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* https://cwe.mitre.org/data/definitions/329.html[MITRE, CWE-329] - CWE-329: Not Using an Unpredictable IV with CBC Mode
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* https://cwe.mitre.org/data/definitions/330.html[MITRE, CWE-330] - Use of Insufficiently Random Values
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* https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38a.pdf[NIST, SP-800-38A] - Recommendation for Block Cipher Modes of Operation
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* Derived from FindSecBugs rule https://find-sec-bugs.github.io/bugs.htm#STATIC_IV[STATIC_IV]
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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include::../message.adoc[]
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'''
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== Comments And Links
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(visible only on this page)
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include::../comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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