Date Discovered August 11, 2009
Description Microsoft Windows is prone to an authentication-bypass vulnerability in the Telnet protocol.
An attacker can exploit this issue to gain unauthorized access to the affected computer with the privileges of the victim. Successful exploits may compromise the affected computer.
Block external access at the network boundary, unless external parties require service. If global access isn't required, filter access to the affected computer at the network boundary. Restricting access to only trusted computers and networks might greatly reduce the likelihood of remote exploits.
Run all software as a nonprivileged user with minimal access rights. To reduce the impact of latent vulnerabilities, run all applications with the minimal amount of privileges required for functionality.
Do not follow links provided by unknown or untrusted sources. Do not follow links provided by untrusted users.
Do not use client software to access unknown or untrusted hosts from critical systems.
Users should be cautious when connecting to suspicious Telnet server shares.
The vendor has released an update. Please see the references for more information.
Credits DilDog of @stake and Beau Butler
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