Cisco Nexus 3000 and 9000 Series Switches Flaw Let Attackers Trigger DoS Attack

A Denial-of-Service vulnerability has been discovered in the Cisco Nexus 3000 and 9000 series switches, which could allow a threat actor to cause a denial-of-service condition due to a flaw in the IS-IS (Intermediate System-to-Intermediate System) protocol.

ISIS is one of the family of IP routing protocols and can also act as an Interior Gateway Protocol (IGP), which is used to distribute IP routing information throughout a very large network that has a single routing policy.

The vulnerability exists due to the unexpected restart of the IS-IS process, causing an infected device to restart. Threat actors can exploit this vulnerability by sending a crafted IS-IS packet to an infected device that can cause the device to reload.

CVE-2023-20169: Cisco Nexus 3000 and 9000 Series Switches IS-IS Protocol Denial of Service Vulnerability

Additionally, there is insufficient input validation when parsing ingress IS-IS packets, leading to this denial of service condition on the affected devices. This vulnerability has been assigned with a CVE ID of CVE-2023-20169 and has a severity of 7.4 (High), as stated by NVD. 

However, there are prerequisites for threat actors to exploit this vulnerability. The threat actor must be layer 2 adjacent to the affected device for successful exploitation. 

Cisco has released a security advisory for this vulnerability, including a list of affected devices and a list of not vulnerable devices.

Affected Products & How to Detect

As mentioned by Cisco, the affected products include Nexus 3000 Series Switches and Nexus 9000 Series Switches in standalone NX-OS mode. In addition, Cisco has also provided steps to detect if a Switch has enabled IS-IS Protocol. 

“A device that is configured for IS-IS authentication can still be affected by this vulnerability. For more information, see Cisco Nexus 9000 Series NX-OS Unicast Routing Configuration Guide, Release 10.3(x): IS-IS Authentication,” reads the security advisory released by Cisco.

The list of products that Cisco has confirmed are not vulnerable can be checked in this Cisco security advisory section.

Keep informed about the latest Cyber Security News by following us on Google News, Linkedin, Twitter, and Facebook.

Eswar

Eswar is a Cyber security content editor with a passion for creating captivating and informative content. With years of experience under his belt in Cyber Security, he is covering Cyber Security News, technology and other news.

Recent Posts

Hackers Use ConnectWise SkyKick Credentials to Access Microsoft 365, Halting Cloud Backups

Attackers abused compromised ConnectWise Cloud Backup credentials to access Microsoft 365 customer environments, prompting ConnectWise…

1 day ago

Anthropic’s Claude AI Uncovers Origins of NSA-Provided Cryptographic Keys After 25 Years

Anthropic says an internal Claude research model reconstructed how the National Security Agency generated seeds…

1 day ago

Critical WordPress Flaws Allow Attackers to Execute Remote Code Without Authentication

Two WordPress Core vulnerabilities can be chained to execute remote code without authentication, according to…

1 day ago

OpenBSD Kernel Flaw Dating Back 37 Years Enables Local Privilege Escalation to Root

A newly disclosed OpenBSD kernel exploitation chain combines a shared memory accounting flaw with a…

1 day ago

GhostAction Hackers Hide Credential-Stealing Malware in Fake Font Files Across 94 GitHub Repositories

GhostAction attackers have expanded their GitHub credential theft campaign with a second stage that disguises…

1 day ago

SideCopy Hackers Target Indian Organizations With ReverseRAT Malware to Steal Data

Indian authorities have warned that SideCopy hackers are targeting Indian organizations, including academic institutions, with…

1 day ago