CVE-2017-12231VulnerabilityPublished 03/03/2022Updated 10/24/2026

CVE-2017-12231: Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability

Affects Cisco IOS softwareSource CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 03/03/2022
KEV deadline: 03/24/2022
EPSS: 7.1% chance of exploitation in 30 days – higher than 94% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2017-12231 (opens in a new tab)

Description

CVE-2017-12231 is a vulnerability in Cisco IOS software's Network Address Translation (NAT) implementation that allows an unauthenticated remote attacker to cause a denial of service. This flaw affects Cisco IOS devices and has been exploited in the wild. No specific affected versions or patch information is provided in the available data.

Summary

This vulnerability involves the NAT functionality in Cisco IOS software where improper implementation allows an unauthenticated remote attacker to trigger a denial of service condition. The vulnerability has been observed to be exploited in the wild, indicating active threat usage. No detailed version or patch information is provided in the source data.

Impact

An unauthenticated remote attacker can cause a denial of service on affected Cisco IOS devices by exploiting this NAT vulnerability. This can disrupt network operations relying on the affected devices. The vulnerability is known to be exploited in the wild, increasing its risk.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official patch or workaround information is provided in the available data.

Weaknesses

CWE-399Unclassified weakness (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 10:26:53 UTC

Weaknesses

References

Related threats