Change to different user, or let different user execute a command

Posted by WG- on Super User See other posts from Super User or by WG-
Published on 2014-08-24T21:59:58Z Indexed on 2014/08/24 22:23 UTC
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Filed under:

linux

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bash

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ssh

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permissions

I have a problem. There is a server which I can access with an account by ssh, lets say WG. Now there is a folder with the following permissions.

drwxr-s---+ 855 vvz www-data 20K Aug 21 17:56 pictures

I want to copy this folder using rsync, however since I am not the user www-data but WG I cannot execute rsync. So I want www-data to execute a rsync command.

However, I do not posses sudo powers. My friend however tells me that I am actually able to execute the rsync command as www-data, but he will not tell me how.

I asked him for some clues and he told me that it had something to do with reverse shell (which I figured out to be that you connect by ssh to your server and then you connect back to your own server, or something). I also asked if it was by-design or actually a flaw in the system. He tells me it is both.

Furthermore I think it has something to do with the group permissions. If I just make sure that I am with the group permissions then I can also read the files.

Anybody has a clue?

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