CVE-2026-76471 Cisco CVE debrief

Who should care

Defenders of Cisco NX-OS Software and Cisco Unified Computing System (Managed) deployments should assess exposure and prioritize patching. This includes network administrators, cybersecurity teams, and IT managers responsible for Cisco NX-OS Software and Unified Computing System (Managed) deployments. They should review Cisco's official advisory, assess potential exposure, and implement compensating controls if patches cannot be immediately applied.

Why it matters

CVE-2026-76471 is a critical vulnerability in Cisco NX-OS Software's NX-API feature, allowing remote code execution or DoS. Defenders should prioritize patching and verify input validation and access controls.

• Potential for remote code execution with root privileges
• Possible denial of service (DoS) condition
• Need for input validation and access controls
• Priority for patching and verification

Technical summary

The vulnerability is in the NX-API feature of Cisco NX-OS Software, allowing unauthenticated remote attackers to execute arbitrary code with root privileges or cause a DoS condition. The exploit involves sending a crafted HTTP request to the NX-API. This feature is used for managing and automating network tasks, making it a high-risk target for attackers. Affected systems likely include Cisco switches and other network devices running NX-OS Software with NX-API enabled. Defenders should focus on validating input to NX-API and securing access controls.

Defensive priority

High

Recommended defensive actions

• Review and apply patches from Cisco
• Restrict access to NX-API
• Monitor for suspicious activity
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and source item provide details on the vulnerability, but limited information is available on affected versions and remediation. Defenders should verify input validation and access controls, review Cisco's official advisory for specific version impacts, and assess potential exposure based on existing NX-OS Software deployments.

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.