title: Cisco IOS XE Software Virtual Fragmentation Reassembly Denial of Service Vulnerability
description: A vulnerability in the implementation of the IPv4 Virtual Fragmentation Reassembly (VFR) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper reassembly of large packets that occurs when VFR is enabled on either a tunnel interface or on a physical interface that is configured with a maximum transmission unit (MTU) greater than 4,615 bytes. An attacker could exploit this vulnerability by sending fragmented packets through a VFR-enabled interface on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
problem types: CWE-416
affected:
{
vendor: Cisco
product: Cisco IOS XE Software
versions:
version: n/a, status: affected
}
metrics:
cvssV3_1: [
version: 3.1
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
attackVector: NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: CHANGED
confidentialityImpact: NONE
integrityImpact: NONE
availabilityImpact: HIGH
baseScore: 8.6
baseSeverity: HIGH
]
exploits: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.