A flaw in the MPLS Operation, Administration, and Maintenance (OAM) handling in Cisco NX-OS Software allows an unauthenticated attacker to send a crafted MPLS echo‑request packet, leading to improper validation that can cause arbitrary code execution with root privileges or a denial‑of‑service condition when the offending process crashes. This is a classic example of CWE‑590, where an attacker exploits the execution of untrusted code paths.

The affected platforms are Cisco NX‑OS Software running on Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches. No specific version range is given, so all current releases that have not applied a patch are considered vulnerable.

The CVSS score of 9.8 marks this vulnerability as critical, indicating that an attacker can remotely achieve full control of the device. EPSS data is not available, but the high CVSS and lack of enforcement limits suggest that the risk remains high. The vulnerability is unauthenticated and network‑directed, meaning any external host that can reach the switch IP space can craft the exploit packet. The assignment of a KEV status of ‘not listed’ does not diminish the potential for exploitation if a public exploit were discovered.