Horizon Alert
Summary of the vulnerability and why it matters
Cisco IOS and IOS XE Software contain a vulnerability within their UDP processing code. This flaw could permit an unauthenticated, remote attacker to disrupt network device operations. Successful exploitation may lead to an interface queue wedge, resulting in a denial-of-service condition for the affected system. This disruption can impede network traffic flow and impact organizational operations.
- Vulnerable Cisco UDP processing
- Unauthenticated remote DoS
- Network device service disruption
Attack Path
How an attacker could exploit the issue
This vulnerability allows an unauthenticated, remote attacker to disrupt network services. The attack exploits how specific Cisco network devices handle UDP packets. By sending crafted UDP packets to a device, an attacker can cause its internal queues to fill up. This condition prevents the device from processing further network traffic, leading to a denial-of-service.
- Network devices are exposed to UDP traffic.
- Attacker sends UDP packets to port zero.
- Device queues fill, causing service disruption.
Live Threat
Current exploitation, exposure, and threat context
This vulnerability could allow an attacker to disrupt network services by causing denial of service conditions on affected Cisco devices. An attacker could exploit this by sending specific UDP packets to an impacted system. This could prevent the device from processing legitimate network traffic, leading to an outage.
- Low skill attacker could exploit.
- Remote, unauthenticated access required.
- Potential for significant network disruption.
Priority actions
Operational Fix
Recommended remediation, mitigation, and detection steps
This vulnerability could allow an unauthenticated, remote attacker to cause a denial of service condition on affected Cisco systems. The attacker could exploit this by sending UDP packets to a specific destination port on an exposed device. This could lead to an interface queue wedge, disrupting network operations. Organizations should prioritize actions to identify and mitigate this risk to maintain service continuity.
- Find affected Cisco assets.
- Reduce exposure or isolate risk.
- Apply vendor fix, verify, and monitor.
