Full Disclosure: Re: Security hole in Confixx backup script

[Valdis.Kletnieks () vt edu]

On Tue, 10 Aug 2004 02:16:24 +0200, Thomas Loch said:
> What if someone creates a shell script that simply "cat /etc/shadow" and sets
> the SetUID flag. Then he makes a backup of that file and restores the backup 
> while he prevents the chown-command anyhow. All files will remain "root". 
> Including the script. The execution of this script will print out the 
> shadowed encrypted passwords. This can even be used to chmod the shadow file 
> and make it readable for everyone
You'd probably have to work a *little* harder than a shell script - most
Unixoid systems don't allow the execution of a setUID shell script due to
various and sundry race conditions involved (which is why 'suidperl' exists).
Other than that, you're on the right track.. ;)

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