Heap-based buffer overflow in Cisco NX-OS Software - CVE-2026-76471
Published: October 9, 2026
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code with root privileges or cause a denial of service.
The vulnerability exists due to a heap-based buffer overflow associated with insufficient input validation in the NX-API feature of Cisco NX-OS Software when processing data sent to the API. A remote attacker can send a crafted HTTP request to the NX-API to execute arbitrary code with root privileges or cause a denial of service.
On Nexus 3000 and 9000 Series Switches, exploitation requires the NX-API feature to be enabled; it is disabled by default. Nexus 9000 Series Switches are affected only in standalone NX-OS mode. On UCS 6300 Series Fabric Interconnects, exploitation requires valid low-privileged user credentials and occurs through the Cisco UCS Manager XML API, which is enabled by default.