In OpenStack Murano through 16.0.0, when YAQL before 3.0.0 is used, the Murano service's MuranoPL extension to the YAQL language fails to sanitize the supplied environment, leading to potential leakage of sensitive service account information.
https://wiki.openstack.org/wiki/OSSN/OSSN-0093
https://opendev.org/openstack/yaql/commit/83e28324e1a0ce3970dd854393d2431123a909d3