CVE-2017-12233 Cisco IOS Software Common Industrial Protocol Request Denial-of-Service

Exploited in the wild High 7.5 Published 28 Sep 2017 Updated 12 Jan 2026

Unauthenticated remote attackers can cause Cisco IOS devices to reload via crafted CIP packets, resulting in a denial of service.

Exploited in the wild: Since 3 Mar 2022
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2017-12233?

CVE-2017-12233 is a high-severity denial of service vulnerability in Cisco Ios, published on 28 Sep 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Multiple vulnerabilities in the implementation of the Common Industrial Protocol (CIP) feature in Cisco IOS 12.4 through 15.6 could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerabilities are due to the improper parsing of crafted CIP packets destined to an affected device. An attacker could exploit these vulnerabilities by sending crafted CIP packets to be processed by an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCuz95334.

Weakness: CWE-20

Which versions are affected by CVE-2017-12233?

It affects 1 product.

Products include Cisco Ios.

How do I fix CVE-2017-12233?

No fix has been published for CVE-2017-12233 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 24 Mar 2022.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2017-12233 being exploited?

Yes. Attackers have exploited CVE-2017-12233 in the wild since at least 3 Mar 2022.

All Cisco Ios vulnerabilities

Sources

Also known as GHSA-h9rm-4rp6-464p.