Cisco has revealed that some of its IP phones are vulnerable to eavesdropping, allowing hackers to remotely listen in to the messages of the firm’s customers.
The problem with the Small Business SPA300 and SPA500 Series of phones is due to "improper authentication" in the default settings of the products, which allows hackers to attack a device by sending a specially crafted XML request.
"An unauthenticated, remote attacker could exploit this vulnerability to listen to a remote audio stream from an affected device or to gain access to make phone calls remotely," Cisco said.
Though the bug has yet to be patched by the vendor, it does not believe it is likely to be exploited.
"To exploit this vulnerability, an attacker may need access to trusted, internal networks behind a firewall to send crafted XML requests to the targeted device," Cisco said. "This access requirement may reduce the likelihood of a successful exploit."
However it added that: "A successful exploit could be used to conduct further attacks."
Later versions of the Cisco Small Business SPA 300 and 500 Series phones are also said to be potentially affected.
Admins are advised to enable XML Execution authentication to guard against the problem, as well as only allow trusted users onto the network or the affected systems.
The bug can also be mitigated against through standard network defences, including "a solid firewall strategy".
