Insecure permissions (777) are set on $HOME/.singularity when it is newly created by Singularity (version from 3.3.0 to 3.5.1), which could lead to an information leak, and malicious redirection of operations performed against Sylabs cloud services.
https://github.com/sylabs/singularity/releases/tag/v3.5.2
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00059.html
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00025.html