Of note, Wieste Venema's telnetd (included in his logdaemon package) is
immune to this attack.
>From the README:
telnetd pretty dumb BSD 4.3 telnetd. No access control or logging,
but compatible with SunOS 4.x, Ultrix 4.x, SunOS 5.x.
Relatively poor in features (no environment passing) so there
is less risks of surprises.
This just might be the quickfix people are looking for. You can find it
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