Horizon Alert
Summary of the vulnerability and why it matters
Certain Cisco network devices are vulnerable to a flaw that can be exploited to disrupt operations. The vulnerability stems from incomplete input validation within the DHCP option 82 encapsulation functionality. An attacker could trigger this flaw by sending a specially crafted DHCP packet, potentially leading to a denial-of-service condition where the affected device reloads, interrupting network services.
- Vulnerable Cisco network devices
- Incomplete input validation flaw
- Denial of service
Attack Path
How an attacker could exploit the issue
This vulnerability allows an attacker to disrupt network services by causing affected devices to reload. The attack exploits incomplete input validation within the software's handling of DHCP option 82 information. By sending specifically crafted DHCPv4 packets, an attacker can trigger a heap overflow, leading to a denial-of-service condition and device reboot.
- Exposure requires DHCP relay functionality.
- Attacker sends crafted DHCPv4 packets.
- Triggering action causes device reload.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability could impact organizations using affected Cisco software. An attacker could potentially cause network devices to reload, disrupting services and leading to a denial of service. This is a significant risk for organizations relying on these devices for network operations.
- Likely attacker skill level: Low
- Required access or conditions: Network access
- Business risk or urgency: High
Priority actions
Operational Fix
Recommended remediation, mitigation, and detection steps
A vulnerability exists in Cisco IOS Software and Cisco IOS XE Software related to DHCP option 82 encapsulation. This issue could permit a remote attacker to cause a denial of service by triggering a device reload. The vulnerability stems from incomplete input validation of DHCPv4 packets, potentially leading to a heap overflow. Exploitation could disrupt network services by causing affected devices to restart.
- Find affected Cisco IOS and IOS XE devices.
- Reduce exposure of vulnerable devices.
- Apply vendor fixes and verify.
- Monitor for related activity.
