Vulnerability · Published Feb 4, 2021 · Assigned by cisco

CVE-2021-1268Cisco IOS XR Software IPv6 Flood Denial of Service Vulnerability

High 7.4

In plain English

A high-severity security flaw in Cisco IOS XR Software from Cisco. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).

Severity (CVSS 3.1)7.4High

Exploit odds (30 days)0.5%top 56.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A vulnerability in the IPv6 protocol handling of the management interfaces of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause an IPv6 flood on the management interface network of an affected device. The vulnerability exists because the software incorrectly forwards IPv6 packets that have an IPv6 node-local multicast group address destination and are received on the management interfaces. An attacker could exploit this vulnerability by connecting to the same network as the management interfaces and injecting IPv6 packets that have an IPv6 node-local multicast group address destination. A successful exploit could allow the attacker to cause an IPv6 flood on the corresponding network. Depending on the number of Cisco IOS XR Software nodes on that network segment, exploitation could cause excessive network traffic, resulting in network degradation or a denial of service (DoS) condition.

Affected products (as reported)

Vendor	Product	Versions
Cisco	Cisco IOS XR Software	n/a

Weakness: CWE-1076 · Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

References

20210203 Cisco IOS XR Software IPv6 Flood Denial of Service Vulnerability vendor-advisory, x_refsource_CISCO