The documents, from the CIA, detailed many vulnerabilities in software from other companies as well, among them Microsoft, Apple, and Google, and also the Linux kernel.
However, in the latter cases, most of the bugs were for older versions of software and had already been fixed.
The company said two factors combined to cause this flaw:
- Failure to restrict the use of CMP-specific telnet options only to internal, local communications between cluster members and instead accept and process such options over any Telnet connection to an affected device; and
- The incorrect processing of malformed CMP-specific telnet options.
"An attacker could exploit this vulnerability by sending malformed CMP-specific telnet options while establishing a telnet session with an affected Cisco device configured to accept Telnet connections," the Cisco advisory said.
"An exploit could allow an attacker to execute arbitrary code and obtain full control of the device or cause a reload of the affected device."
A list of the 318 devices affected is on the Cisco website. The company said it would release fixes, adding that there were no workarounds.