Cisco warns of bug that lets attackers break traffic encryption

Cisco warned customers today of a high-severity vulnerability impacting some data center switch models and allowing attackers to tamper with encrypted traffic.

Tracked as CVE-2023-20185, the flaw was found during internal security testing in the ACI Multi-Site CloudSec encryption feature of data center Cisco Nexus 9000 Series Fabric Switches.

The vulnerability only impacts Cisco Nexus 9332C, 9364C, and 9500 spine switches only if they are in ACI mode, are part of a Multi-Site topology, have the CloudSec encryption feature enabled, and are running firmware 14.0 and later releases.

To find out if CloudSec encryption is being used across an ACI site, go to Infrastructure > Site Connectivity > Configure > Sites > site-name > Inter-Site Connectivity on the Cisco Nexus Dashboard Orchestrator and check if “CloudSec Encryption” is marked as “Enabled.”

To check whether CloudSec encryption is enabled on a Cisco Nexus 9000 Series switch, run the show cloudsec sa interface all command via the switch command line.

Cisco warns of critical switch bugs with public exploit code.

Share this article on social media:

Subscribe to Our Newsletter!
Stay on top of cybersecurity risks, evolving threats and industry news.
This field is for validation purposes and should be left unchanged.

The Latest Cybersecurity News

From major cyberattacks, newly discovered critical vulnerabilities to recommended best practices, read it here first:

Tell us About your Needs
Get an Answer the Same Business Day

Got an urgent request? Call us at 1-877-805-7475 or Book a meeting.

What happens next:

A Vumetric expert will contact you to learn more about your cybersecurity needs and goals.

The project's scope will be defined (Target environment, deadlines, requirements, etc.)

A detailed quote including all-inclusive pricing and statement of work is sent to you.

This field is for validation purposes and should be left unchanged.


Everything You Need to Know

Gain confidence in your future cybersecurity assessments by learning to effectively plan, scope and execute projects.


Enter your Email Address

This field is for validation purposes and should be left unchanged.

* No free email provider (e.g:,, etc.)

This site is registered on as a development site. Switch to a production site key to remove this banner.