#cisco

A vulnerability in the IPv6 DHCP version 6 (DHCPv6) relay and server features of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to insufficient validation of data boundaries. An attacker could exploit this vulnerability by sending crafted DHCPv6 messages to an affected device. A successful exploit could allow the attacker to cause the device to reload unexpectedly.

A vulnerability in the fragmentation handling code of tunnel protocol packets in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected system to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to the improper handling of large fragmented tunnel protocol packets. One example of a tunnel protocol is Generic Routing Encapsulation (GRE). An attacker could exploit this vulnerability by sending crafted fragmented packets to an affected system. A successful exploit could allow the attacker to cause the affected system to reload, resulting in a DoS condition. Note: Only traffic directed to the affected system can be used to exploit this vulnerability.

A vulnerability in the IPv6 DHCP (DHCPv6) client module of Cisco Adaptive Security Appliance (ASA) Software, Cisco Firepower Threat Defense (FTD) Software, Cisco IOS Software, and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of DHCPv6 messages. An attacker could exploit this vulnerability by sending crafted DHCPv6 messages to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Note: To successfully exploit this vulnerability, the attacker would need to either control the DHCPv6 server or be in a man-in-the-middle position.

A vulnerability in the CLI of Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to execute arbitrary commands with elevated privileges. This vulnerability is due to insufficient input validation by the system CLI. An attacker with privileges to run commands could exploit this vulnerability by first authenticating to an affected device using either local terminal access or a management shell interface and then submitting crafted input to the system CLI. A successful exploit could allow the attacker to execute commands on the underlying operating system with root-level privileges. An attacker with limited user privileges could use this vulnerability to gain complete control over the system. Note: For additional information about specific impacts, see the Details section of this advisory.

A vulnerability in the implementation of the Cisco Network Plug-and-Play (PnP) agent of Cisco DNA Center could allow an authenticated, remote attacker to view sensitive information in clear text. The attacker must have valid low-privileged user credentials. This vulnerability is due to improper role-based access control (RBAC) with the integration of PnP. An attacker could exploit this vulnerability by authenticating to the device and sending a query to an internal API. A successful exploit could allow the attacker to view sensitive information in clear text, which could include configuration files.

A vulnerability in the management CLI of Cisco access point (AP) software could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation of commands supplied by the user. An attacker could exploit this vulnerability by authenticating to a device and submitting crafted input to the affected command. A successful exploit could allow the attacker to cause an affected device to reload spontaneously, resulting in a DoS condition.

A vulnerability in the management API of Cisco DNA Center could allow an authenticated, remote attacker to elevate privileges in the context of the web-based management interface on an affected device. This vulnerability is due to the unintended exposure of sensitive information. An attacker could exploit this vulnerability by inspecting the responses from the API. Under certain circumstances, a successful exploit could allow the attacker to access the API with the privileges of a higher-level user account. To successfully exploit this vulnerability, the attacker would need at least valid Observer credentials.

A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker to perform a directory traversal and access resources that are outside the filesystem mountpoint of the web UI. This vulnerability is due to an insufficient security configuration. An attacker could exploit this vulnerability by sending a crafted request to the web UI. A successful exploit could allow the attacker to gain read access to files that are outside the filesystem mountpoint of the web UI. Note: These files are located on a restricted filesystem that is maintained for the web UI. There is no ability to write to any files on this filesystem.

A vulnerability in Cisco IOS XE Software for Cisco Catalyst 9300 Series Switches could allow an authenticated, local attacker with level-15 privileges or an unauthenticated attacker with physical access to the device to execute persistent code at boot time and break the chain of trust. This vulnerability is due to errors that occur when retrieving the public release key that is used for image signature verification. An attacker could exploit this vulnerability by modifying specific variables in the Serial Peripheral Interface (SPI) flash memory of an affected device. A successful exploit could allow the attacker to execute persistent code on the underlying operating system. Note: In Cisco IOS XE Software releases 16.11.1 and later, the complexity of an attack using this vulnerability is high. However, an attacker with level-15 privileges could easily downgrade the Cisco IOS XE Software on a device to a release that would lower the attack complexity.

A vulnerability in the web-based management interface of Cisco SD-WAN vManage Software could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected system. This vulnerability is due to insufficient CSRF protections for the web-based management interface on an affected system. An attacker could exploit this vulnerability by persuading a user of the interface to click a malicious link. A successful exploit could allow the attacker to perform arbitrary actions with the privilege level of the affected user. These actions could include modifying the system configuration and deleting accounts.