由于安全领域变化之快, 每天有新的漏洞被公布, 而入侵者正不断设计新的攻击和安 置后门技术, 安枕无忧的安全技术是没有的.请记住没有简单的防御,只有不懈的努力! ( Be aware that no defense is foolproof, and that there is no substitute for diligent attention. 此句该如何翻译? :( )
On Unix machines, placing commands into the .forward file was also a common method of regaining access. For the account ``username‘‘ a .forward file might be constructed as follows:
permutations of this method include alteration of the systems mail aliases file (most commonly located at /etc/aliases). Note that this is a simple permutation, the more advanced can run a simple script from the forward file that can take arbitrary commands via stdin (after minor preprocessing).
PS: The above method is also useful gaining access a companies mailhub (assuming there is a shared a home directory FS on &nbs>
the client and server).
> Using smrsh can effectively negate this backdoor (although it‘s quite > possibly still a problem if you allow things like elm‘s filter or > procmail which can run programs themselves...).