The bulk of the high-severity vulnerabilities are tied to conditions that could lead to denial-of-service attacks. One Cisco bug impacting its 800 and 1000 series routers had a CVSS severity score of 9.9.9. Another bug (CVE-2019-12648) could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service condition, Cisco wrote. The bugs also include a warning to users of its L2 traceroute feature in IOS for which there is public exploit code.
Source: https://threatpost.com/cisco-high-severity-bugs-2/148706/