CVE-2026-20221 | Cisco Cyber Vision GRE Tunnel Decapsulation denial of service

A vulnerability, which was classified as very critical, has been found in Cisco Cyber Vision, Open Source Snort3, Secure Firewall Threat Defense Software, UDT SNORT IPS Engine Software and Umbrella Insights Virtual Appliance. Affected by this issue is some unknown functionality of the component GRE Tunnel Decapsulation. Performing a manipulation results in denial of service.

This vulnerability is reported as CVE-2026-20221. The attack is possible to be carried out remotely. No exploit exists.

It is advisable to upgrade the affected component.VulDB Recent EntriesRead More