A vulnerability in the implementation of the system login block-for command for Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a login process to unexpectedly restart, causing a denial of service (DoS) condition. This vulnerability is due to a logic error in the implementation of the system login block-for command when an attack is detected and acted upon. An attacker could exploit this vulnerability by performing a brute-force login attack on an affected device. A successful exploit could allow the attacker to cause a login process to reload, which could result in a delay during authentication to the affected device.

A vulnerability in the way Cisco UCS Manager software handles SSH sessions could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper resource management for established SSH sessions. An attacker could exploit this vulnerability by opening a significant number of SSH sessions on an affected device. A successful exploit could allow the attacker to cause a crash and restart of internal Cisco UCS Manager software processes and a temporary loss of access to the Cisco UCS Manager CLI and web UI. Note: The attacker must have valid user credentials to authenticate to the affected device.

A vulnerability in the network stack of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability exists because the software improperly releases resources when it processes certain IPv6 packets that are destined to an affected device. An attacker could exploit this vulnerability by sending multiple crafted IPv6 packets to an affected device. A successful exploit could cause the network stack to run out of available buffers, impairing operations of control plane and management plane protocols and resulting in a DoS condition. Manual intervention would be required to restore normal operations on the affected device. For more information about the impact of this vulnerability, see the Details section of this advisory.

A vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to execute arbitrary code with administrative privileges or cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending crafted Cisco UDLD protocol packets to a directly connected, affected device. A successful exploit could allow the attacker to execute arbitrary code with administrative privileges or cause the Cisco UDLD process to crash and restart multiple times, causing the affected device to reload and resulting in a DoS condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. The attacker needs full control of a directly connected device. That device must be connected over a port channel that has UDLD enabled. To trigger arbitrary code…

A vulnerability in the certificate registration process of Cisco Unified Computing System (UCS) Central Software could allow an authenticated, adjacent attacker to register a rogue Cisco Unified Computing System Manager (UCSM). This vulnerability is due to improper certificate validation. An attacker could exploit this vulnerability by sending a crafted HTTP request to the registration API. A successful exploit could allow the attacker to register a rogue Cisco UCSM and gain access to Cisco UCS Central Software data and Cisco UCSM inventory data.

IP-in-IP protocol specifies IP Encapsulation within IP standard (RFC 2003, STD 1) that decapsulate and route IP-in-IP traffic is vulnerable to spoofing, access-control bypass and other unexpected behavior due to the lack of validation to verify network packets before decapsulation and routing.

A vulnerability in the firmware of the Cisco UCS C-Series Rack Servers could allow an authenticated, physical attacker to bypass Unified Extensible Firmware Interface (UEFI) Secure Boot validation checks and load a compromised software image on an affected device. The vulnerability is due to improper validation of the server firmware upgrade images. An attacker could exploit this vulnerability by installing a server firmware version that would allow the attacker to disable UEFI Secure Boot. A successful exploit could allow the attacker to bypass the signature validation checks that are done by UEFI Secure Boot technology and load a compromised software image on the affected device. A compromised software image is any software image that has not been digitally signed by Cisco.

A vulnerability in a specific CLI command within the local management (local-mgmt) context for Cisco UCS Fabric Interconnect Software could allow an authenticated, local attacker to gain elevated privileges as the root user on an affected device. The vulnerability is due to extraneous subcommand options present for a specific CLI command within the local-mgmt context. An attacker could exploit this vulnerability by authenticating to an affected device, entering the local-mgmt context, and issuing a specific CLI command and submitting user input. A successful exploit could allow the attacker to execute arbitrary operating system commands as root on an affected device. The attacker would need to have valid user credentials for the device.

A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Software could allow an authenticated, remote attacker to inject arbitrary commands that are executed with root privileges on an affected device. An attacker would need to have valid administrator credentials on the device. The vulnerability is due to insufficient validation of user-supplied input by the affected software. An attacker with elevated privileges could exploit this vulnerability by sending crafted commands to the administrative web management interface of the affected software. A successful exploit could allow the attacker to inject and execute arbitrary, system-level commands with root privileges on an affected device.

A vulnerability in the web server of Cisco Integrated Management Controller (IMC) could allow an unauthenticated, remote attacker to cause the web server process to crash, causing a denial of service (DoS) condition on an affected system. The vulnerability is due to insufficient validation of user-supplied input on the web interface. An attacker could exploit this vulnerability by submitting a crafted HTTP request to certain endpoints of the affected software. A successful exploit could allow an attacker to cause the web server to crash. Physical access to the device may be required for a restart.