A serious flaw in Cisco Systems’ switch software puts computer networks at risk of cyber attack.
A vulnerability in Cisco's Internetwork Operating System (IOS) could be exploited by remote attackers to crash or run malicious code on devices that run IOS.
IOS runs on Cisco's routers and switches, which make up a large portion of the internet's infrastructure, as well as being used across enterprises.
In an advisory note, Cisco said, "Successful exploitation of the vulnerability on Cisco IOS may result in a reload of the device or execution of arbitrary code. Repeated exploitation could result in a sustained denial of service attack.”
The flaw does not affect all versions of IOS. Cisco has issued a patch to protect IOS versions 12.2ZH, 12.2ZL, 12.3, 12.3T, 12.4 and 12.4T.