Cisco warns of a flaw in some of its network switches that could expose encrypted traffic between data centers.

In a blog, Cisco states that these are only Nexus 9332C, 9364C and 9500 switches running firmware version 14.0 or newer. The bug itself is due to CloudSec, a feature that encrypts traffic across the network switches. Now the feature does the opposite, leaving sensitive data in data centers open and accessible to outsiders. Attackers could intercept the traffic and crack the encryption.

According to Cisco, there is currently no evidence that the vulnerability is actively being exploited. But now that the bug is public knowledge, that could soon change. Cisco therefore recommends preemptively disabling the CloudSec feature, as it now does more harm than good to the security of your data.

Turn off CloudSec

If you are using one of the above Cisco switches, open the management dashboard and go through the following menus: Infrastructure > Site Connectivity > Configure > Sites > site name > Inter-Site Connectivity. In the last window you can see whether CloudSec encryption is activated and can then deactivate it again. Another option is to run the command Show all Cloudsec interfaces in your switch prompt.

A patch for the vulnerability does not appear to be imminent. Vulnerabilities in Cisco networking products are common. The network supplier recently warned of vulnerable adapters for analog phones.