CVE-2021-1377

Cisco IOS and IOS XE Software ARP Resource Management Exhaustion Denial of Service Vulnerability

Description

A vulnerability in Address Resolution Protocol (ARP) management of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to prevent an affected device from resolving ARP entries for legitimate hosts on the connected subnets. This vulnerability exists because ARP entries are mismanaged. An attacker could exploit this vulnerability by continuously sending traffic that results in incomplete ARP entries. A successful exploit could allow the attacker to cause ARP requests on the device to be unsuccessful for legitimate hosts, resulting in a denial of service (DoS) condition.

Category

5.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2021-1377?
CVE-2021-1377 has been scored as a medium severity vulnerability.
How to fix CVE-2021-1377?
To fix CVE-2021-1377, 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-2021-1377 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1377 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1377?
CVE-2021-1377 affects Cisco Cisco IOS.
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