A vulnerability in the Layer 2 punt code of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a queue wedge on an interface that receives specific Layer 2 frames, resulting in a denial of service (DoS) condition. This vulnerability is due to improper handling of certain Layer 2 frames. An attacker could exploit this vulnerability by sending specific Layer 2 frames on the segment the router is connected to. A successful exploit could allow the attacker to cause a queue wedge on the interface, resulting in a DoS condition.

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) support for the AutoReconnect feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to exhaust the free IP addresses from the assigned local pool. This vulnerability occurs because the code does not release the allocated IP address under certain failure conditions. An attacker could exploit this vulnerability by trying to connect to the device with a non-AnyConnect client. A successful exploit could allow the attacker to exhaust the IP addresses from the assigned local pool, which prevents users from logging in and leads to a denial of service (DoS) condition.

A vulnerability in the H.323 application level gateway (ALG) used by the Network Address Translation (NAT) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass the ALG. This vulnerability is due to insufficient data validation of traffic that is traversing the ALG. An attacker could exploit this vulnerability by sending crafted traffic to a targeted device. A successful exploit could allow the attacker to bypass the ALG and open connections that should not be allowed to a remote device located behind the ALG. Note: This vulnerability has been publicly discussed as NAT Slipstreaming.

A vulnerability in Ethernet over GRE (EoGRE) packet processing of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9800 Family Wireless Controller, Embedded Wireless Controller, and Embedded Wireless on Catalyst 9000 Series Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper processing of malformed EoGRE packets. An attacker could exploit this vulnerability by sending malicious packets to the affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

A vulnerability in the CLI command permissions of Cisco IOS and Cisco IOS XE Software could allow an authenticated, local attacker to retrieve the password for Common Industrial Protocol (CIP) and then remotely configure the device as an administrative user. This vulnerability exists because incorrect permissions are associated with the show cip security CLI command. An attacker could exploit this vulnerability by issuing the command to retrieve the password for CIP on an affected device. A successful exploit could allow the attacker to reconfigure the device.

A vulnerability in Cisco IOx application hosting environment of Cisco IOS XE Software could allow an authenticated, remote attacker to inject commands into the underlying operating system as the root user. This vulnerability is due to incomplete validation of fields in the application packages loaded onto IOx. An attacker could exploit this vulnerability by creating a crafted application .tar file and loading it onto the device. A successful exploit could allow the attacker to perform command injection into the underlying operating system as the root user.

A vulnerability in the CLI of Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to inject arbitrary commands to be executed with root privileges on the underlying operating system. This vulnerability is due to insufficient input validation on certain CLI commands. An attacker could exploit this vulnerability by authenticating to the device and submitting crafted input to the CLI. The attacker must be authenticated as an administrative user to execute the affected commands. A successful exploit could allow the attacker to execute commands with root privileges.

Multiple Cisco products are affected by a vulnerability in the Snort application detection engine that could allow an unauthenticated, remote attacker to bypass the configured policies on an affected system. The vulnerability is due to a flaw in the detection algorithm. An attacker could exploit this vulnerability by sending crafted packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured policies and deliver a malicious payload to the protected network.

Multiple Cisco products are affected by a vulnerability with TCP Fast Open (TFO) when used in conjunction with the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect detection of the HTTP payload if it is contained at least partially within the TFO connection handshake. An attacker could exploit this vulnerability by sending crafted TFO packets with an HTTP payload through an affected device. A successful exploit could allow the attacker to bypass configured file policy for HTTP packets and deliver a malicious payload.

Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of an HTTP range header. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass configured file policy for HTTP packets and deliver a malicious payload.

A vulnerability in the packet filtering features of Cisco SD-WAN Software could allow an unauthenticated, remote attacker to bypass L3 and L4 traffic filters. The vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by crafting a malicious TCP packet with specific characteristics and sending it to a targeted device. A successful exploit could allow the attacker to bypass the L3 and L4 traffic filters and inject an arbitrary packet into the network.

A vulnerability in the web server authentication of Cisco IOS XE Software could allow an authenticated, remote attacker to crash the web server on the device. The vulnerability is due to insufficient input validation during authentication. An attacker could exploit this vulnerability by entering unexpected characters during a valid authentication. A successful exploit could allow the attacker to crash the web server on the device, which must be manually recovered by disabling and re-enabling the web server.

A vulnerability in the web UI of Cisco IOS and Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected system. The vulnerability is due to insufficient CSRF protections for the web UI on an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to follow a malicious link. A successful exploit could allow the attacker to perform arbitrary actions with the privilege level of the targeted user. If the user has administrative privileges, the attacker could alter the configuration, execute commands, or reload an affected device.

A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software and Cisco IOS XE Software on Catalyst 4500 Series Switches could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to insufficient input validation when the software processes specific SNMP object identifiers. An attacker could exploit this vulnerability by sending a crafted SNMP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: To exploit this vulnerability by using SNMPv2c or earlier, the attacker must know the SNMP read-only community string for an affected system. To exploit this vulnerability by using SNMPv3, the attacker must know the user credentials for the affected system.

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) implementation in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to prevent IKEv2 from establishing new security associations. The vulnerability is due to incorrect handling of crafted IKEv2 SA-Init packets. An attacker could exploit this vulnerability by sending crafted IKEv2 SA-Init packets to the affected device. An exploit could allow the attacker to cause the affected device to reach the maximum incoming negotiation limits and prevent further IKEv2 security associations from being formed.

A vulnerability in Security Group Tag Exchange Protocol (SXP) in Cisco IOS Software, Cisco IOS XE Software, and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability exists because crafted SXP packets are mishandled. An attacker could exploit this vulnerability by sending specifically crafted SXP packets to the affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Multiple vulnerabilities in the implementation of the Common Industrial Protocol (CIP) feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerabilities are due to insufficient input processing of CIP traffic. An attacker could exploit these vulnerabilities by sending crafted CIP traffic to be processed by an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

A vulnerability in software image verification in Cisco IOS XE Software could allow an unauthenticated, physical attacker to install and boot a malicious software image or execute unsigned binaries on an affected device. The vulnerability is due to an improper check on the area of code that manages the verification of the digital signatures of system image files during the initial boot process. An attacker could exploit this vulnerability by loading unsigned software on an affected device. A successful exploit could allow the attacker to install and boot a malicious software image or execute unsigned binaries on the targeted device.

A vulnerability in the Tool Command Language (Tcl) interpreter of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, local attacker with privileged EXEC credentials to execute arbitrary code on the underlying operating system (OS) with root privileges. The vulnerability is due to insufficient input validation of data passed to the Tcl interpreter. An attacker could exploit this vulnerability by loading malicious Tcl code on an affected device. A successful exploit could allow the attacker to cause memory corruption or execute the code with root privileges on the underlying OS of the affected device.

A vulnerability in the Secure Shell (SSH) server code of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. The vulnerability is due to an internal state not being represented correctly in the SSH state machine, which leads to an unexpected behavior. An attacker could exploit this vulnerability by creating an SSH connection to an affected device and using a specific traffic pattern that causes an error condition within that connection. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.