Potential fix for code scanning alert no. 73: Use of a broken or risky cryptographic algorithm

[davewichers]

Potential fix for https://github.com/aspectsecurity/TestCodeQL/security/code-scanning/73

In general, the fix is to replace the weak DES algorithm with a strong modern cipher such as AES, and to ensure that key sizes and IV sizes match the requirements of the chosen algorithm. Specifically, we should change both the Cipher transformation string and the KeyGenerator algorithm name from "DES" to an AES variant, and adjust the IV length from 8 bytes (DES block size) to 16 bytes (AES block size). The rest of the logic (encrypting the input and writing it to a file) can remain unchanged.

The best targeted fix without changing existing functionality is:

• Update the IV generation to produce 16 bytes instead of 8: random.generateSeed(16).
• Change the cipher acquisition from Cipher.getInstance("DES/CBC/PKCS5PADDING", ...) to Cipher.getInstance("AES/CBC/PKCS5PADDING", ...).
• Change the key generator from KeyGenerator.getInstance("DES") to KeyGenerator.getInstance("AES").
• Optionally, explicitly set a key size (e.g., 128 bits) for clarity; however, many JREs default to 128 bits for AES, so we can leave it implicit to minimize changes if desired. I’ll keep the fix minimal and rely on the default.

All required classes (Cipher, KeyGenerator, IvParameterSpec, SecureRandom) are already referenced with fully qualified names, so we do not need to modify imports. Edits are confined to src/main/java/org/owasp/benchmark/testcode/Benchmark00684.java in the shown region around the IV generation, cipher initialization, and key generation.

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