Thank you for reporting this. It seems that used SFTP library uses too wide permissions by default.
I have checked and it seems that when we have implemented SFTP support their documentation does not state about such default permissions. Also we did not spot this issue, because it seems that our VPS server used for tests forces lower permissions for files (it is possible to force permissions for files uploaded via sftp/scp protocol).
I have prepared a fix which after uploading files set their chmods to 0644 and for folders set chmods 0755. It will be available in Publii v.0.42.1 which will be probably released at nearest Monday.
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