A vulnerability in the logic that handles access control to one of the hardware components in Cisco's proprietary Secure Boot implementation could allow an authenticated, local attacker to write a modified firmware image to the component. This vulnerability affects multiple Cisco products that support hardware-based Secure Boot functionality. The vulnerability is due to an improper check on the area of code that manages on-premise updates to a Field Programmable Gate Array (FPGA) part of the Secure Boot hardware implementation. An attacker with elevated privileges and access to the underlying operating system that is running on the affected device could exploit this vulnerability by writing a modified firmware image to the FPGA. A successful exploit could either cause the device to become unusable (and require a hardware replacement) or allow tampering with the Secure Boot verification process, which under some circumstances may allow the attacker to install and boot a malicious software image. An attacker will need to fulfill all the following conditions to attempt to exploit this vulnerability: Have privileged administrative access to the device. Be able to access the underlying operating system running on the device; this can be achieved either by using a supported, documented mechanism or by exploiting another vulnerability that would provide an attacker with such access. Develop or have access to a platform-specific exploit. An attacker attempting to exploit this vulnerability across multiple affected platforms would need to research each one of those platforms and then develop a platform-specific exploit. Although the research process could be reused across different platforms, an exploit developed for a given hardware platform is unlikely to work on a different hardware platform.
A vulnerability in the Hot Standby Router Protocol (HSRP) subsystem of Cisco IOS and IOS XE Software could allow an unauthenticated, adjacent attacker to receive potentially sensitive information from an affected device. The vulnerability is due to insufficient memory initialization. An attacker could exploit this vulnerability by receiving HSRPv2 traffic from an adjacent HSRP member. A successful exploit could allow the attacker to receive potentially sensitive information from the adjacent device.
A vulnerability in the VLAN Trunking Protocol (VTP) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to corrupt the internal VTP database on an affected device and cause a denial of service (DoS) condition. The vulnerability is due to a logic error in how the affected software handles a subset of VTP packets. An attacker could exploit this vulnerability by sending VTP packets in a sequence that triggers a timeout in the VTP message processing code of the affected software. A successful exploit could allow the attacker to impact the ability to create, modify, or delete VLANs and cause a DoS condition. There are workarounds that address this vulnerability. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS Software or Cisco IOS XE Software, are operating in VTP client mode or VTP server mode, and do not have a VTP domain name configured. The default configuration for Cisco devices that are running Cisco IOS Software or Cisco IOS XE Software and support VTP is to operate in VTP server mode with no domain name configured.
Multiple vulnerabilities in the CLI parser of Cisco IOS XE Software could allow an authenticated, local attacker to inject arbitrary commands into the CLI of the affected software, which could allow the attacker to gain access to the underlying Linux shell of an affected device and execute commands with root privileges on the device. The vulnerabilities exist because the affected software does not sufficiently sanitize command arguments before passing commands to the Linux shell for execution. An attacker could exploit these vulnerabilities by submitting a malicious CLI command to the affected software. A successful exploit could allow the attacker to break from the CLI of the affected software, which could allow the attacker to gain access to the underlying Linux shell on an affected device and execute arbitrary commands with root privileges on the device. Cisco Bug IDs: CSCuz03145, CSCuz56419, CSCva31971, CSCvb09542.
A vulnerability in the Forwarding Information Base (FIB) code of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, network attacker to cause a denial of service (DoS) condition. The vulnerability is due to a limitation in the way the FIB is internally representing recursive routes. An attacker could exploit this vulnerability by injecting routes into the routing protocol that have a specific recursive pattern. The attacker must be in a position on the network that provides the ability to inject a number of recursive routes with a specific pattern. An exploit could allow the attacker to cause an affected device to reload, creating a DoS condition. Cisco Bug IDs: CSCva91655.
Multiple vulnerabilities in the web-based user interface (web UI) of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the web UI of the affected software. The vulnerabilities are due to insufficient input validation of certain parameters that are passed to the affected software via the web UI. An attacker could exploit these vulnerabilities by persuading a user of the affected UI to access a malicious link or by intercepting a user request for the affected UI and injecting malicious code into the request. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected UI or allow the attacker to access sensitive browser-based information on the user's system. Cisco Bug IDs: CSCuz38591, CSCvb09530, CSCvb10022.
Multiple vulnerabilities in the CLI parser of Cisco IOS XE Software could allow an authenticated, local attacker to inject arbitrary commands into the CLI of the affected software, which could allow the attacker to gain access to the underlying Linux shell of an affected device and execute commands with root privileges on the device. The vulnerabilities exist because the affected software does not sufficiently sanitize command arguments before passing commands to the Linux shell for execution. An attacker could exploit these vulnerabilities by submitting a malicious CLI command to the affected software. A successful exploit could allow the attacker to break from the CLI of the affected software, which could allow the attacker to gain access to the underlying Linux shell on an affected device and execute arbitrary commands with root privileges on the device. Cisco Bug IDs: CSCuz03145, CSCuz56419, CSCva31971, CSCvb09542.
A vulnerability in the Cisco IOS XE Software REST API could allow an authenticated, remote attacker to bypass API authorization checks and use the API to perform privileged actions on an affected device. The vulnerability is due to insufficient authorization checks for requests that are sent to the REST API of the affected software. An attacker could exploit this vulnerability by sending a malicious request to an affected device via the REST API. A successful exploit could allow the attacker to selectively bypass authorization checks for the REST API of the affected software and use the API to perform privileged actions on an affected device. Cisco Bug IDs: CSCuz56428.
Format String vulnerability in the Link Layer Discovery Protocol (LLDP) subsystem of Cisco IOS Software, Cisco IOS XE Software, and Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges on an affected device. Cisco Bug IDs: CSCvd73664.
Multiple vulnerabilities in the CLI parser of Cisco IOS XE Software could allow an authenticated, local attacker to inject arbitrary commands into the CLI of the affected software, which could allow the attacker to gain access to the underlying Linux shell of an affected device and execute commands with root privileges on the device. The vulnerabilities exist because the affected software does not sufficiently sanitize command arguments before passing commands to the Linux shell for execution. An attacker could exploit these vulnerabilities by submitting a malicious CLI command to the affected software. A successful exploit could allow the attacker to break from the CLI of the affected software, which could allow the attacker to gain access to the underlying Linux shell on an affected device and execute arbitrary commands with root privileges on the device. Cisco Bug IDs: CSCuz03145, CSCuz56419, CSCva31971, CSCvb09542.