CVE-2021-34713

Cisco IOS XR Software for ASR 9000 Series Routers Denial of Service Vulnerability

Description

A vulnerability in the Layer 2 punt code of Cisco IOS XR Software running on Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to cause the affected line card to reboot. This vulnerability is due to incorrect handling of specific Ethernet frames that cause a spin loop that can make the network processors unresponsive. An attacker could exploit this vulnerability by sending specific types of Ethernet frames on the segment where the affected line cards are attached. A successful exploit could allow the attacker to cause the affected line card to reboot.

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.10%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XR Software
Published at:
Updated at:

References

Link Tags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-npspin-QYpwdhFD vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-34713?
CVE-2021-34713 has been scored as a high severity vulnerability.
How to fix CVE-2021-34713?
To fix CVE-2021-34713, 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-2021-34713 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34713 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-2021-34713?
CVE-2021-34713 affects Cisco Cisco IOS XR Software.
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