Vulnerability in Cisco iOS

CVE-2021-1377

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.

EPSS: 0.014 (71.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-1377?
CVE-2021-1377 is a medium-severity vulnerability in Cisco iOS, classified under CWE-399. CVSS score: 5.8/10. Published 2021-03-24.
How severe is CVE-2021-1377?
Medium severity. CVSS v3 base score is 5.8 out of 10.