CVE-2021-1268

Cisco IOS XR Software IPv6 Flood Denial of Service Vulnerability

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.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XR Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-1268?
CVE-2021-1268 has been scored as a high severity vulnerability.
How to fix CVE-2021-1268?
To fix CVE-2021-1268, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-1268 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1268 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1268?
CVE-2021-1268 affects Cisco Cisco IOS XR Software.
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