This week, Cisco released its semi-annual IOS and IOS XE software security advisory bundle, which fixes ten vulnerabilities—six of which are classified as being of “high severity.” The most significant ones are three security flaws that remote, unauthenticated attackers can leverage to establish a denial-of-service (DoS) situation.
The first of these problems, identified as CVE-2023-20080, affects the IPv6 DHCP version 6 (DHCPv6) relay and server functionality of IOS and IOS XE software. Due to insufficient data boundary validation, an attacker can transmit forged DHCPv6 signals to a vulnerable device and force an unexpected device reload.