Bugtraq: Re: majordomo local exploit

[atatat () ATATDOT NET (Andrew Brown)]

> This patch should take care of that problem:
>
> --- majordomo.old       Sat Oct  2 02:30:30 1999
> +++ majordomo   Thu Dec 30 04:34:25 1999
> @@ -44,6 +44,25 @@
>     die("$cf not readable; stopped");
> }
>
> +# Check if the cf file is owned by effective uid
> +if ((stat($cf))[4] != $>) {
> +    die("$cf not owned by effective uid; stopped");
> +}
> ...
> Comments?
hmm...race condition?

it would really be better (in this vein) to (a) open the config file,
(b) fstat it (once, not twice) and (c) then read and eval the code
rather using require (since you can't "require" a file handle).

of course...using a config file or perl is nice, since you *can*
simply require it, but a parsed config file that just sets variables
is better since it implicitly disallows attacks like this.

--
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