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-2018-0172
HighCVSS 8.6KEVSummary
A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS and IOS XE Software allows an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS). It exists because the software performs incomplete input validation of option 82 information in DHCPv4 packets from DHCP relay agents. Sending a crafted DHCPv4 packet can cause a heap overflow and device reload.
Risk Assessment
An attacker can remotely trigger a reload of a Cisco device, causing network service disruption. In production environments this means network unavailability and impact on critical applications.
Recommendation
Upgrade Cisco IOS/IOS XE software to a version containing the fix for Cisco Bug ID CSCvg62730. Consider restricting trusted DHCP relay agents and monitoring for unusual DHCPv4 traffic.
Other vulnerabilities in Cisco IOS Software and Cisco IOS XE Software
See all- CVE-2018-0171CriticalActively exploited
A vulnerability in the Smart Install feature of Cisco IOS and IOS XE Software is caused by improper validation of packet data. An unauthenticated remote attacker can send a crafted Smart Install message to TCP port 4786, causing a buffer overflow that may lead to device reload, arbitrary code execution, or a watchdog crash.
- CVE-2018-0159HighActively exploited
A vulnerability in the IKEv1 implementation of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS). It is due to improper validation of specific IKEv1 packets. Sending crafted IKEv1 packets during IKE negotiation can cause a device reload.
- CVE-2018-0158HighActively exploited
A vulnerability in the IKEv2 module of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause a memory leak or a reload of an affected device, leading to a denial of service (DoS). It is due to incorrect processing of certain IKEv2 packets. Sending crafted IKEv2 packets can cause continuous memory consumption and eventual device reload.
- CVE-2018-0156HighActively exploited
A vulnerability in the Smart Install feature of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS). It is due to improper validation of packet data. Sending a crafted packet to TCP port 4786 can cause a device reload. Only Smart Install client switches are affected, not Smart Install directors.
- CVE-2018-0151CriticalActively exploited
A vulnerability in the QoS subsystem of Cisco IOS and IOS XE Software is due to incorrect bounds checking of values in packets destined for UDP port 18999. An unauthenticated remote attacker can send malicious packets, causing a buffer overflow that may lead to arbitrary code execution with elevated privileges or a device reload.
Original NVD description (English source)
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 a heap overflow condition on the affected device, which will cause the device to reload and result in a DoS condition. Cisco Bug IDs: CSCvg62730.