An issue was discovered in Yealink Configuration Encrypt Tool (AES version) and Yealink Configuration Encrypt Tool (RSA version before 1.2). There is a single hardcoded key (used to encrypt provisioning documents) across customers' installations.

Yealink Config Encrypt Tool add RSA before 1.2 has a built-in RSA key pair, and thus there is a risk of decryption by an adversary.