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terminal server security hole??


I just found a security issue to manage Cisco routers and need your help!

Currently we use a terminal server manage a few core devices.

For example, Cisco 2509 terminal server has 8 terminal line(s). The terminal line connects to other router?s console port. Different people have read or write access to those 8 routers

Terminal server (A) ====-> Router (B) console port

I have write access to the router (know the enable password). If I use a computer and telnet into the terminal server (A), then from the terminal server (A) telnet into the Router (B) and login to enable mode. Now if I press Ctrl+Shift+6 then X. I can back to terminal server (A). Then I type ?exit? and log out of terminal server (A). The problem is here that the session between terminal server (A) and router (B) still on.

At this time, if a low access user login to terminal server (A) then telnet to Router (B), he can directly go into enable mode. The router will not ask the use enable password. I have put ?exec-timeout 5 0? and ?session-timeout 5? under router (B) console port. But there is still 5 minutes security hole and could let the low access right people into router (B) enable mode.

My question is how to secure those 5 minutes?

Hall of Fame Super Silver

Re: terminal server security hole??


The simple solution to your situation is that after you enter the Ctrl+Shift+6 then X then you enter disconnect (you can abbreviate it as disc) and it will terminate the reverse telnet. Then no other user will be able to get in on your session and your router is secured.



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