Permissions, Privileges, and Access Controls
common/snapshots.py in Back In Time (aka backintime) 0.9.26 changes certain permissions to 0777 before deleting the files in an old backup snapshot, which allows local users to obtain sensitive information by reading these files, or interfere with backup integrity by modifying files that are shared across snapshots.
CWE-264 - Permissions Privileges and Access Controls
CWE 264 (permissions, privileges, and access controls) is not a weakness in and of itself, rather it is a category of weaknesses related to the management of permissions, privileges, and other security features used to perform access control. If not addressed, the weaknesses in this category allow attackers to gain privileges for an unintended sphere of control, access sensitive information, and execute arbitrary commands.