CVE-2026-76486 Cisco CVE debrief

Who should care

Network administrators and security teams responsible for managing and securing Cisco Nexus 3000 and 9000 Series Switches should assess exposure and implement recommended actions to mitigate this vulnerability.

Why it matters

CVE-2026-76486 is a critical vulnerability in Cisco Nexus 3000 and 9000 Series Switches that allows for remote code execution or Denial-of-Service conditions. Network administrators and security teams must assess exposure and implement recommended actions to mitigate this vulnerability.

• Potential for remote code execution with root privileges, allowing for complete control of affected devices.
• Possible disruption of service due to Denial-of-Service (DoS) conditions.
• Need for immediate assessment and remediation due to critical severity.
• Potential for lateral movement within the network if exploited.

Technical summary

The vulnerability is due to improper input validation of IP traffic when the NGOAM feature is enabled on Cisco Nexus 3000 and 9000 Series Switches. An attacker could exploit this vulnerability by sending crafted packets to an IP interface on an affected device. A successful exploit could allow the attacker to execute arbitrary code with root privileges and could cause process crashes resulting in a reload and Denial-of-Service (DoS) condition. This vulnerability affects multiple versions of Cisco NX-OS Software running on these switches, and Cisco has provided a security advisory detailing the affected versions and recommended actions.

Defensive priority

High priority for immediate assessment and remediation due to critical severity and potential for remote code execution.

Recommended defensive actions

• Immediately assess exposure of Cisco Nexus 3000 and 9000 Series Switches to this vulnerability.
• Verify if any devices are running affected versions of Cisco NX-OS Software.
• Apply patches or updates provided by Cisco to remediate the vulnerability.
• Implement compensating controls such as network segmentation or traffic filtering to limit exposure.
• Monitor for suspicious activity or indicators of compromise.

Evidence notes

The vulnerability is confirmed in multiple versions of Cisco NX-OS Software running on Cisco Nexus 3000 and 9000 Series Switches. Cisco has provided a security advisory detailing the affected versions and recommended actions.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.