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Re: Making the keyboard work

On Sat, Feb 21, 2009 at 10:46:58PM -0500, Thor Lancelot Simon wrote:
 > I don't know what remote systems' sshds are likely to with $TERMCAP;

Historically, $TERMCAP is not propagated because it's unsafe; most
legacy termcap libraries are full of overflows, and also you can use
it to read arbitrary files, which can create various problems with
e.g. restricted accounts.

With telnet, the way $TERM was theoretically supposed to be propagated
required telnetd to be linked against termcap, with the result that
accepting $TERMCAP caused termcap to see it long before login ran and
allowed assorted remote root exploits. Presumably sshd is not so
stupid; however, paranoia tends to linger.

David A. Holland

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