CVE-2017-12231Actively exploitedAdded to KEV 2022-03-03

Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability

Cisco, IOS software

Description

A vulnerability in the implementation of Network Address Translation (NAT) functionality in Cisco IOS could allow an unauthenticated, remote attacker to cause a denial of service.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Medium

7.1%

estimated chance of real-world exploitation in the next 30 days, higher than 94.2% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2022-03-24

CWE-399

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