The clone_file function in transfer.c in Augeas before 1.0.0, when copy_if_rename_fails is set and EXDEV or EBUSY is returned by the rename function, allows local users to overwrite arbitrary files and obtain sensitive information via a bind mount on the (1) .augsave or (2) destination file when using the backup save option, or (3) .augnew file when using the newfile save option.
