For AES-256 encryption in Mendix 10.24, you don't necessarily need a Marketplace module. You can implement it using a custom Java Action.
A common approach is:
Example approach:
AES/CBC/PKCS5Padding
or preferably:
AES/GCM/NoPadding
(GCM provides both encryption and integrity checking.)
The flow would be:
Mendix API
→ Microflow
→ Java Action (Encrypt)
→ Return encrypted value
For the key:
For example:
Key + Salt/IV
|
↓
AES-256 Cipher
|
↓
Encrypted Base64 string
Then create another Java Action for decryption using the same key and IV.
The PGP modules in Marketplace are mainly for public/private key encryption. AES is symmetric encryption, so custom Java implementation is usually the cleaner option.
Also, avoid using the same static IV for every encryption. Generate a new IV for every encrypted value and store/transmit it along with the encrypted data.
Kindly mark this as the accepted answer if it helps.