Cisco recently warned of a security flaw in its IronPort Email Security Appliances and IronPort Security Management Appliances.

"The vulnerability could be exploited by an attacker to remotely execute code on a system by sending a specially crafted command to the telnet daemon (telnetd)," The H Security reports.

"A buffer overflow in the encrypt_keyid() function causes the server to execute the injected code with system privileges," the article states. "Cisco has yet to provide its customers with a patch. Users who wish to prevent their systems from being compromised need to deactivate the Telnet server – instructions for doing so can be found in the advisory."

Go to "Cisco Security Appliances at risk from Telnet bug" to read the details.

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