Our dashboards now have hundreds, if not thousands of these messages.
A security vulnerability was discovered within the local status page of the MR, MS, and MX product lines. The vulnerability allows an attacker to inject configuration options and data into the device. The attacker would require either physical access or local network access and knowledge of the credentials for the local status page to exploit this vulnerability. Meraki has released firmware for all affected products. We strongly recommend that affected customers promptly upgrade their devices’ firmware to our latest Stable build which contains patches for this issue. We’ve built a document detailing the issue as well.
They can only be dismissed one at a time, which is very frustrating.
I also have this problem. The dashboard seems to be incorrectly recognizing the MX appliances as MS switches with old firmware versions. I checked every MX by hand and verified that each had the minimum firmware version installed that patched this vulnerability. As I was putting in a ticket, I refreshed the dashboard and all the alerts disappeared; however, on the "Organization > Monitor > Firmware Upgrades" page, it still lists the MX appliances as running MS firmware.
There was a bug in the script that generated the banners alerting affected customers to this issue. It has since been resolved and the correct number of banners - just one! - should now be displayed. My apologies for the noise and I hope you didn't spend too much time clicking all of these away.