zhmcclient is a pure Python client library for the IBM Z HMC Web Services API. In affected versions the Python package "zhmcclient" writes password-like properties in clear text into its HMC and API logs in the following cases: 1. The 'boot-ftp-password' and 'ssc-master-pw' properties when creating or updating a partition in DPM mode, in the zhmcclient API and HMC logs. 2. The 'ssc-master-pw' and 'zaware-master-pw' properties when updating an LPAR in classic mode, in the zhmcclient API and HMC logs. 3. The 'ssc-master-pw' and 'zaware-master-pw' properties when creating or updating an image activation profile in classic mode, in the zhmcclient API and HMC logs. 4. The 'password' property when creating or updating an HMC user, in the zhmcclient API log. 5. The 'bind-password' property when creating or updating an LDAP server definition, in the zhmcclient API and HMC logs. This issue affects only users of the zhmcclient package that have enabled the Python loggers named "zhmcclient.api" (for the API log) or "zhmcclient.hmc" (for the HMC log) and that use the functions listed above. This issue has been fixed in zhmcclient version 1.18.1. Users are advised to upgrade. There are no known workarounds for this vulnerability.