A vulnerability in the Cisco TrustSec (CTS) Protected Access Credential (PAC) provisioning module of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of attributes in RADIUS messages. An attacker could exploit this vulnerability by sending a malicious RADIUS message to an affected device while the device is in a specific state.

A vulnerability in the filesystem resource management code of Cisco IOS XE Software could allow an unauthenticated, remote attacker to exhaust filesystem resources on an affected device and cause a denial of service (DoS) condition. The vulnerability is due to ineffective management of the underlying filesystem resources. An attacker could exploit this vulnerability by performing specific actions that result in messages being sent to specific operating system log files. A successful exploit could allow the attacker to exhaust available filesystem space on an affected device. This could cause the device to crash and reload, resulting in a DoS condition for clients whose network traffic is transiting the device. Upon reload of the device, the impacted filesystem space is cleared, and the device will return to normal operation. However, continued exploitation of this vulnerability could cause subsequent forced crashes and reloads, which could lead to an extended DoS condition.

A vulnerability in the egress MPLS packet processing function of Cisco IOS XE Software for Cisco Catalyst 3650, Catalyst 3850, and Catalyst 9000 Family Switches could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to insufficient input validation of IPv4 traffic. An attacker could exploit this vulnerability by sending a malformed packet out of an affected MPLS-enabled interface. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the password-recovery disable feature of Cisco IOS XE ROM Monitor (ROMMON) Software for Cisco Catalyst Switches could allow an unauthenticated, local attacker to recover the configuration or reset the enable password. This vulnerability is due to a problem with the file and boot variable permissions in ROMMON. An attacker could exploit this vulnerability by rebooting the switch into ROMMON and entering specific commands through the console. A successful exploit could allow the attacker to read any file or reset the enable password.