Code reviewHardcr-g245

Subject Crypto misuseLevel Senior–Staff~30 minCommon in Security interviewsIndustries Software development

Question

Review this Java AES helper used to encrypt user records.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

Learn the concepts

Talk through your review

Code to reviewjava

1private static final byte[] IV = new byte[16]; // all zeros2private static final SecretKeySpec KEY = loadKey();3 4public static byte[] encrypt(byte[] plaintext) throws Exception {5    Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");6    c.init(Cipher.ENCRYPT_MODE, KEY, new IvParameterSpec(IV));7    return c.doFinal(plaintext);8}

Run or narrate your approach, then ask the coach.