Cisco IOS and IOS XE Software IPv6 Hop-by-Hop Options Denial of Service Vulnerability

A vulnerability in the IPv6 processing code of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect handling of specific IPv6 hop-by-hop options. An attacker could exploit this vulnerability by sending a malicious IPv6 packet to or through the affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition on an affected device.

Cisco IOS XE Software Web UI Denial of Service Vulnerability

A vulnerability in the web user interface of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a double-free-in-memory handling by the affected software when specific HTTP requests are processed. An attacker could exploit this vulnerability by sending specific HTTP requests to the web user interface of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device. To exploit this vulnerability, the attacker must have access to the management interface of the affected software, which is typically connected to a restricted management network.

Cisco IOS XE Software HTTP Denial of Service Vulnerability

A vulnerability in the web framework of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a buffer overflow condition on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to the affected software improperly parsing malformed HTTP packets that are destined to a device. An attacker could exploit this vulnerability by sending a malformed HTTP packet to an affected device for processing. A successful exploit could allow the attacker to cause a buffer overflow condition on the affected device, resulting in a DoS condition.

Cisco IOS XE Software Cisco Discovery Protocol Memory Leak Vulnerability

A vulnerability in the Cisco Discovery Protocol (CDP) module of Cisco IOS XE Software Releases 16.6.1 and 16.6.2 could allow an unauthenticated, adjacent attacker to cause a memory leak that may lead to a denial of service (DoS) condition. The vulnerability is due to incorrect processing of certain CDP packets. An attacker could exploit this vulnerability by sending certain CDP packets to an affected device. A successful exploit could cause an affected device to continuously consume memory and eventually result in a memory allocation failure that leads to a crash, triggering a reload of the affected device.

Cisco IOS XE Software and Cisco ASA 5500-X Series Adaptive Security Appliance IPsec Denial of Service Vulnerability

A vulnerability in the IPsec driver code of multiple Cisco IOS XE Software platforms and the Cisco ASA 5500-X Series Adaptive Security Appliance (ASA) could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to improper processing of malformed IPsec Authentication Header (AH) or Encapsulating Security Payload (ESP) packets. An attacker could exploit this vulnerability by sending malformed IPsec packets to be processed by an affected device. An exploit could allow the attacker to cause a reload of the affected device.

Cisco IOS and IOS XE Software Cluster Management Protocol Denial of Service Vulnerability

A vulnerability in the implementation of the cluster feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to improper input validation when handling Cluster Management Protocol (CMP) messages. An attacker could exploit this vulnerability by sending a malicious CMP message to an affected device. A successful exploit could allow the attacker to cause the switch to crash and reload or to hang, resulting in a DoS condition. If the switch hangs it will not reboot automatically, and it will need to be power cycled manually to recover.

Cisco IOS XE Software NAT Session Initiation Protocol Application Layer Gateway Denial of Service Vulnerability

A vulnerability in the Network Address Translation (NAT) Session Initiation Protocol (SIP) Application Layer Gateway (ALG) of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper processing of SIP packets in transit while NAT is performed on an affected device. An unauthenticated, remote attacker could exploit this vulnerability by sending crafted SIP packets via UDP port 5060 through an affected device that is performing NAT for SIP packets. A successful exploit could allow an attacker to cause the device to reload, resulting in a denial of service (DoS) condition.

Cisco IOS XE Software Command Injection Vulnerabilities

A vulnerability in the CLI parser of Cisco IOS XE Software could allow an authenticated, local attacker to execute commands on the underlying Linux shell of an affected device with root privileges. The vulnerability exist because the affected software improperly sanitizes command arguments, failing to prevent access to certain internal data structures on an affected device. An attacker who has privileged EXEC mode (privilege level 15) access to an affected device could exploit these vulnerabilities on the device by executing CLI commands that contain custom arguments. A successful exploit could allow the attacker to execute arbitrary commands with root privileges on the affected device.

Cisco IOS XE Software Errdisable Denial of Service Vulnerability

A vulnerability in the errdisable per VLAN feature of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause the device to crash, leading to a denial of service (DoS) condition. The vulnerability is due to a race condition that occurs when the VLAN and port enter an errdisabled state, resulting in an incorrect state in the software. An attacker could exploit this vulnerability by sending frames that trigger the errdisable condition. A successful exploit could allow the attacker to cause the affected device to crash, leading to a DoS condition.

Cisco IOS XE Software Command Injection Vulnerabilities

A vulnerability in the CLI parser of Cisco IOS XE Software could allow an authenticated, local attacker to execute commands on the underlying Linux shell of an affected device with root privileges. The vulnerability exist because the affected software improperly sanitizes command arguments, failing to prevent access to certain internal data structures on an affected device. An attacker who has privileged EXEC mode (privilege level 15) access to an affected device could exploit these vulnerabilities on the device by executing CLI commands that contain custom arguments. A successful exploit could allow the attacker to execute arbitrary commands with root privileges on the affected device.

Cisco IOS and IOS XE Software SM-1T3/E3 Service Module Denial of Service Vulnerability

A vulnerability in the SM-1T3/E3 firmware on Cisco Second Generation Integrated Services Routers (ISR G2) and the Cisco 4451-X Integrated Services Router (ISR4451-X) could allow an unauthenticated, remote attacker to cause the ISR G2 Router or the SM-1T3/E3 module on the ISR4451-X to reload, resulting in a denial of service (DoS) condition on an affected device. The vulnerability is due to improper handling of user input. An attacker could exploit this vulnerability by first connecting to the SM-1T3/E3 module console and entering a string sequence. A successful exploit could allow the attacker to cause the ISR G2 Router or the SM-1T3/E3 module on the ISR4451-X to reload, resulting in a DoS condition on an affected device.

Cisco IOS XE Software Privileged EXEC Mode Root Shell Access Vulnerability

A vulnerability in the CLI parser of Cisco IOS XE Software could allow an authenticated, local attacker to gain access to the underlying Linux shell of an affected device and execute arbitrary commands with root privileges on the device. The vulnerability is due to the affected software improperly sanitizing command arguments to prevent modifications to the underlying Linux filesystem on a device. An attacker who has privileged EXEC mode (privilege level 15) access to an affected device could exploit this vulnerability on the device by executing CLI commands that contain crafted arguments. A successful exploit could allow the attacker to gain access to the underlying Linux shell of the affected device and execute arbitrary commands with root privileges on the device.

Cisco IOS and IOS XE Software TACACS+ Client Denial of Service Vulnerability

A vulnerability in the TACACS+ client subsystem 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 vulnerability is due to improper handling of crafted TACACS+ response packets by the affected software. An attacker could exploit this vulnerability by injecting a crafted TACACS+ packet into an existing TACACS+ session between an affected device and a TACACS+ server or by impersonating a known, valid TACACS+ server and sending a crafted TACACS+ packet to an affected device when establishing a connection to the device. To exploit this vulnerability by using either method, the attacker must know the shared TACACS+ secret and the crafted packet must be sent in response to a TACACS+ request from a TACACS+ client. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Cisco IOS XE Software Shell Access Authentication Bypass Vulnerability

A vulnerability in the shell access request mechanism of Cisco IOS XE Software could allow an authenticated, local attacker to bypass authentication and gain unrestricted access to the root shell of an affected device. The vulnerability exists because the affected software has insufficient authentication mechanisms for certain commands. An attacker could exploit this vulnerability by requesting access to the root shell of an affected device, after the shell access feature has been enabled. A successful exploit could allow the attacker to bypass authentication and gain unrestricted access to the root shell of the affected device.

Cisco IOS XE Software MACsec MKA Using EAP-TLS Authentication Bypass Vulnerability

A vulnerability in the MACsec Key Agreement (MKA) using Extensible Authentication Protocol-Transport Layer Security (EAP-TLS) functionality of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to bypass authentication and pass traffic through a Layer 3 interface of an affected device. The vulnerability is due to a logic error in the affected software. An attacker could exploit this vulnerability by connecting to and passing traffic through a Layer 3 interface of an affected device, if the interface is configured for MACsec MKA using EAP-TLS and is running in access-session closed mode. A successful exploit could allow the attacker to bypass 802.1x network access controls and gain access to the network.

Cisco IOS and IOS XE Software Cisco Discovery Protocol Denial of Service Vulnerability

A vulnerability in the implementation of Cisco Discovery Protocol functionality in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust memory on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper memory handling by the affected software when the software processes high rates of Cisco Discovery Protocol packets that are sent to a device. An attacker could exploit this vulnerability by sending a high rate of Cisco Discovery Protocol packets to an affected device. A successful exploit could allow the attacker to exhaust memory on the affected device, resulting in a DoS condition.

Cisco IOS XE Software Digital Signature Verification Bypass Vulnerability

A vulnerability in the Image Verification feature of Cisco IOS XE Software could allow an authenticated, local attacker to install a malicious software image or file on an affected device. The vulnerability is due to the affected software improperly verifying digital signatures for software images and files that are uploaded to a device. An attacker could exploit this vulnerability by uploading a malicious software image or file to an affected device. A successful exploit could allow the attacker to bypass digital signature verification checks for software images and files and install a malicious software image or file on the affected device.

A vulnerability in the Wireless Network Control daemon (wncd) of Cisco IOS XE Software for Wireless LAN Controllers could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition. This vulnerability is due to improper memory management. An attacker could exploit this vulnerability by sending a series of network requests to an affected device. A successful exploit could allow the attacker to cause the wncd process to consume available memory and eventually cause the device to reload, resulting in a DoS condition.

Cisco IOS and IOS XE Software TCP Denial of Service Vulnerability

A vulnerability in the TCP socket code of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a state condition between the socket state and the transmission control block (TCB) state. While this vulnerability potentially affects all TCP applications, the only affected application observed so far is the HTTP server. An attacker could exploit this vulnerability by sending specific HTTP requests at a sustained rate to a reachable IP address of the affected software. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition on an affected device.

Cisco IOS and IOS XE Software Cluster Management Protocol Denial of Service Vulnerability

A vulnerability in the Cluster Management Protocol (CMP) processing code in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation when processing CMP management packets. An attacker could exploit this vulnerability by sending malicious CMP management packets to an affected device. A successful exploit could cause the switch to crash, resulting in a DoS condition. The switch will reload automatically.