A critical vulnerability exists in the MPLS OAM feature of Cisco NX-OS Software on Nexus 3000 and 9000 Series Switches. This flaw allows an unauthenticated, remote attacker to execute arbitrary code with root privileges or induce a denial of service. The vulnerability stems from improper validation of MPLS echo-request packets. An attacker can exploit this by sending a specially crafted echo-request to an affected device's IP address. Successful exploitation grants root access and may lead to process crashes. This can further result in device reloads, causing a denial of service. Cisco has released software updates to mitigate this vulnerability. No workarounds are available to address this specific issue. This advisory, available on Cisco's security center, is part of a larger group of advisories. Further details on fixes are documented in the Cisco NX-OS Software Security Hardening Release. The vulnerability is identified as CVE-2026-76465.