A vulnerability in the web interface of Cisco Small Business 200, 300, and 500 Series Managed Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper validation of requests sent to the web interface. An attacker could exploit this vulnerability by sending a malicious request to the web interface of an affected device. A successful exploit could allow the attacker to cause an unexpected reload of the device, resulting in a DoS condition.

A vulnerability in the Secure Sockets Layer (SSL) input packet processor of Cisco Small Business 200, 300, and 500 Series Managed Switches could allow an unauthenticated, remote attacker to cause a memory corruption on an affected device. The vulnerability is due to improper validation of HTTPS packets. An attacker could exploit this vulnerability by sending a malformed HTTPS packet to the management web interface of the affected device. A successful exploit could allow the attacker to cause an unexpected reload of the device, resulting in a denial of service (DoS) condition.

A vulnerability in the interactions between the DHCP and TFTP features for Cisco Small Business 300 Series (Sx300) Managed Switches could allow an unauthenticated, remote attacker to cause the device to become low on system memory, which in turn could lead to an unexpected reload of the device and result in a denial of service (DoS) condition on an affected device. The vulnerability is due to a failure to free system memory when an unexpected DHCP request is received. An attacker could exploit this vulnerability by sending a crafted DHCP packet to the targeted device. A successful exploit could allow the attacker to cause an unexpected reload of the device.

A vulnerability in the Simple Network Management Protocol (SNMP) input packet processor of Cisco Small Business Sx200, Sx300, Sx500, ESW2 Series Managed Switches and Small Business Sx250, Sx350, Sx550 Series Switches could allow an authenticated, remote attacker to cause the SNMP application of an affected device to cease processing traffic, resulting in the CPU utilization reaching one hundred percent. Manual intervention may be required before a device resumes normal operations. The vulnerability is due to improper validation of SNMP protocol data units (PDUs) in SNMP packets. An attacker could exploit this vulnerability by sending a malicious SNMP packet to an affected device. A successful exploit could allow the attacker to cause the device to cease forwarding traffic, which could result in a denial of service (DoS) condition. Cisco has released firmware updates that address this vulnerability.

A vulnerability in the Secure Shell (SSH) authentication process of Cisco Small Business Switches software could allow an attacker to bypass client-side certificate authentication and revert to password authentication. The vulnerability exists because OpenSSH mishandles the authentication process. An attacker could exploit this vulnerability by attempting to connect to the device via SSH. A successful exploit could allow the attacker to access the configuration as an administrative user if the default credentials are not changed. There are no workarounds available; however, if client-side certificate authentication is enabled, disable it and use strong password authentication. Client-side certificate authentication is disabled by default.

A vulnerability in the Cisco Small Business Switches software could allow an unauthenticated, remote attacker to bypass the user authentication mechanism of an affected device. The vulnerability exists because under specific circumstances, the affected software enables a privileged user account without notifying administrators of the system. An attacker could exploit this vulnerability by using this account to log in to an affected device and execute commands with full admin rights. Cisco has not released software updates that address this vulnerability. This advisory will be updated with fixed software information once fixed software becomes available. There is a workaround to address this vulnerability.

A vulnerability in the web-based management interface of Cisco Small Business 300 Series Managed Switches could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the interface of an affected system. The vulnerability exists because the affected management interface performs insufficient validation of user-supplied input. 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 execute arbitrary script code in the context of the affected interface or allow the attacker to access sensitive, browser-based information.

A vulnerability in the web-based management interface of Cisco Small Business 300 Series (Sx300) Managed Switches could allow an authenticated, remote attacker to conduct a persistent cross-site scripting (XSS) attack against a user of the web-based management interface of an affected device. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or allow the attacker to access sensitive browser-based information. Cisco Bug IDs: CSCvi87326.

A vulnerability in the web-based management interface of Cisco Small Business 300 Series (Sx300) Managed Switches could allow an authenticated, remote attacker to conduct a reflected cross-site scripting (XSS) attack against a user of the web-based management interface of an affected device. The vulnerability is due to insufficient validation of user-supplied input by the web-based management interface of an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or allow the attacker to access sensitive browser-based information. Cisco Bug IDs: CSCvi87330.

A vulnerability in the web framework of Cisco Small Business Managed Switches software could allow an unauthenticated, remote attacker to conduct an HTTP response splitting attack against a user of the web interface of an affected system. The vulnerability is due to insufficient input validation of some parameters that are passed to the web server of the affected system. An attacker could exploit this vulnerability by convincing a user to follow a malicious link or by intercepting a user request 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 web interface or allow the attacker to access sensitive browser-based information. This vulnerability affects the following Cisco Small Business 300 and 500 Series Managed Switches: Cisco 350 Series Managed Switches, Cisco 350X Series Stackable Managed Switches, Cisco 550X Series Stackable Managed Switches, Cisco ESW2 Series Advanced Switc…