Actively exploited in the wild
Cisco IOS and IOS XE Software Improper Input Validation Vulnerability
Cisco - IOS and IOS XE Software · Listed in the CISA KEV since 2022-03-03. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2018-0173
HighCVSS 8.6KEVSummary
A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.
Risk Assessment
An attacker can remotely cause a device reload, resulting in a disruption of network services.
Recommendation
Apply Cisco updates for bug ID CSCvg62754.
Other vulnerabilities in Cisco IOS Software
See all- CVE-2018-0180MediumActively exploited
Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later.
- CVE-2018-0179MediumActively exploited
Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected system, resulting in a denial of service (DoS) condition. These vulnerabilities affect Cisco devices running Cisco IOS Software Release 15.4(2)T, 15.4(3)M, or 15.4(2)CG and later.
- CVE-2018-0175HighActively exploited
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.
- CVE-2018-0174HighActively exploited
A vulnerability in the DHCP option 82 encapsulation functionality 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 exists because the affected software performs incomplete input validation of option 82 information that it receives in DHCP Version 4 (DHCPv4) packets from DHCP relay agents. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCuh91645.
- CVE-2018-0161MediumActively exploited
A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software running on certain models of Cisco Catalyst Switches could allow an authenticated, remote attacker to cause a denial of service (DoS) condition, aka a GET MIB Object ID Denial of Service Vulnerability. The vulnerability occurs when the affected software processes an SNMP read request containing a request for the ciscoFlashMIB object ID, which could cause the device to restart due to a SYS-3-CPUHOG. This affects Cisco Catalyst 2960-L Series Switches, Cisco Catalyst Digital Building Series Switches 8P and 8U running SNMPv2 or SNMPv3.
Original NVD description (English source)
A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.