To ensure security, WeChat Pay uses AES-256-GCMencryption for key information in the callback notification and platform certificate download API. API V3 key is a symmetric key used in encryption.
Merchants need to set the key in Merchant Platform > API Security so that the request can pass the signature verification of WeChat Pay. The length of the key is 32 bytes.
Notice
The API V3 key and the API key are isolated. Setting the key will not cause changes to the API key.
Notice
The API V3 key is sensitive. Please keep it safe and do not disclose it. If you suspect information has been leaked, please reset the key.
