Wednesday, October 14, 2026

Cisco NX-OS Vulnerability Allows Attackers to Bypass Image Signature Verification

A critical vulnerability has been identified in the bootloader of Cisco NX-OS Software, potentially allowing attackers to bypass image signature verification.

This flaw, which affects several Cisco product lines, could enable unauthorized users to load unverified software onto affected devices.

The vulnerability is attributed to insecure bootloader settings within the Cisco NX-OS Software. Exploitation of this flaw requires either physical access to the device or administrative credentials from a local attacker.

By executing specific bootloader commands, an attacker can bypass the image signature verification process, a crucial security measure designed to ensure that only authenticated software is executed on network devices.

Free Webinar on Best Practices for API vulnerability & Penetration Testing:  Free Registration

Affected Products

The vulnerability impacts a range of Cisco products that utilize secure boot technology. The affected product lines include:

  • MDS 9000 Series Multilayer Switches
  • Nexus 3000, 7000, and 9000 Series Switches
  • UCS 6400 and 6500 Series Fabric Interconnects

It is important to note that only devices running a vulnerable BIOS version of Cisco NX-OS Software are susceptible. Customers can determine their BIOS version by using the show version command on their devices.

Currently, there are no workarounds for this vulnerability. Cisco has emphasized the importance of applying the available software updates to mitigate potential risks. The company has released updates that address this security issue and recommends customers upgrade their systems promptly.

Cisco has provided free software updates for all affected products. Customers with active service contracts can obtain these updates through their usual channels. For those without service contracts, updates can be accessed by contacting the Cisco Technical Assistance Center (TAC).

To resolve the vulnerability, affected systems require a BIOS update. The specific steps include upgrading the Cisco NX-OS Software on impacted devices using the install all CLI command or installing a specific Software Maintenance Upgrade (SMU) as indicated in the advisory’s Fixed Release table.

The Cisco Product Security Incident Response Team (PSIRT) has not reported any public exploitation of this vulnerability to date. Ferdinand Nölscher from Google Cloud Product Security Engineering initially reported the issue, highlighting the collaborative efforts in identifying and addressing security threats.

This vulnerability underscores the importance of maintaining up-to-date software and implementing robust security practices within network infrastructures. Organizations using Cisco NX-OS Software should prioritize reviewing their systems for vulnerabilities and apply necessary patches to safeguard against potential attacks.

Leveraging 2024 MITRE ATT&CK Results for SME & MSP Cybersecurity Leaders – Attend Free Webinar

Gurubaran
Gurubaran
Gurubaran is a co-founder of Cyber Security News and GBHackers On Security. He has 10+ years of experience as a Security Consultant, Editor, and Analyst in cybersecurity, technology, and communications.

Hot this week

How To Access Dark Web Anonymously and know its Secretive and Mysterious Activities

What is Deep Web The deep web, invisible web, or...

How to Build and Run a Security Operations Center (SOC Guide) – 2023

Today’s Cyber security operations center (CSOC) should have everything...

Russian Hackers Bypass EDR to Deliver a Weaponized TeamViewer Component

TeamViewer's popularity and remote access capabilities make it an...

Web Server Penetration Testing Checklist – 2026

Web server pentesting is performed under three significant categories: identity,...

ATM Penetration Testing – Advanced Testing Methods to Find The Vulnerabilities

ATM Penetration testing, Hackers have found different approaches to...

Criminal IP to Showcase Threat Intelligence and AITEM at Security Days Fall 2026 Tokyo

Torrance, California, October 13th, 2026, CyberNewswire Criminal IP, developed by...

G2A.COM Reports 35% Growth in Security Software Orders, Outpacing VPN Growth

Amsterdam, Netherlands, October 13th, 2026, CyberNewswire Antivirus and security software...

Hackers Target Hundreds of French Supermarkets, Heating Refrigeration Systems to 50°C

Hundreds of French supermarkets experienced refrigeration disruptions after hackers...

SAP Patches Critical NetWeaver and S/4HANA Security Flaws Affecting Enterprise Systems

SAP’s Security Patch Day on October 13, 2026, addresses...

Attackers Can Hijack npm Packages Without Stealing Developer Credentials

A flaw in npm’s Trusted Publishing mechanism could let...

Anthropic Warns AI Models Could Soon Self-Replicate Across Smart TVs and IoT Devices

Anthropic researchers have raised concerns that small artificial intelligence...

New macOS Malware Uses Fake System Prompts to Steal Passwords and Deploy RAT

A newly marketed macOS malware-as-a-service platform, ICMacOS, is using...

Hackers Exploit Citrix NetScaler Zero-Days to Deploy Modified Platypus Backdoor

Threat actors are exploiting two critical zero-day vulnerabilities in...

Related Articles

Recent News