CVE-2017-12231
Cisco IOS Software Network Address Translation Denial-of-Service Vulnerability
What is affected
| Vendor | Cisco |
|---|---|
| Product | IOS software |
| Weakness | CWE-399 |
The vulnerability
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.
Required action
Apply updates per vendor instructions.
US federal civilian agencies were required to act by 24 March 2022 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.
Where this comes from
Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 11 Nov 2026, 21:30. Nothing here is our own assessment. For the technical scoring, see the NVD record below.
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