KAON routers with hard‑coded root credentials: unauthenticated attackers could seize control — patch the CG3000T/CG3000TC now

KAON routers with hard‑coded root credentials: unauthenticated attackers could seize control — patch the CG3000T/CG3000TC now

If you own a KAON CG3000TC or CG3000T router, this is not the day to say “we’ll sort it later.” A newly disclosed vulnerability (CVE-2025-7072) reveals hard‑coded credentials stored in clear text and shared across all devices of these models. An unauthenticated remote attacker could use those credentials to execute commands with root privileges. The issue is rated 9.3 (CRITICAL) and fixes are available in firmware 1.00.67 for CG3000TC and 1.00.27 for CG3000T.

What happened (brief, factual recap)

The firmware in KAON CG3000TC and CG3000T routers contains hard‑coded credentials in clear text that are shared across devices of these models, creating a single predictable key that an unauthenticated remote attacker could use to gain root command execution. The vendor has issued fixed firmware versions: 1.00.67 for CG3000TC and 1.00.27 for CG3000T. The vulnerability was reported minutes ago and is scored as CRITICAL (9.3).

Why this matters to your business

Routers are the gateways between your network and the internet, and root access on a router is equivalent to a burglar getting the keys to the building and the security‑control panel. An attacker with root on a business router can reroute traffic, inspect or modify sensitive communications, implant persistent backdoors, pivot to internal systems and quietly harvest credentials or data.

The immediate victims are customers and staff whose traffic traverses the affected devices; downstream impacts include disrupted services, stolen or tampered data, regulatory scrutiny and a very awkward conversation with insurers, partners and the board. If those routers sit at branch sites, in home‑working kits or inside supplier networks, the blast radius grows fast.

What could happen if you ignore it

Ignore this and you risk scenarios that make boardrooms sweat: persistent, unnoticed interception of confidential data; attackers building a reliable beachhead for later ransomware or espionage; or intermittent outages and degraded performance while investigators poke around. Recovery costs — forensic analysis, legal fees, notification obligations and remediation — typically dwarf the cost of a prompt firmware update or device replacement.

How an information security programme would have reduced the risk

This is exactly the sort of flaw that a disciplined information security management system (ISMS) would catch earlier or contain more effectively. An ISO 27001 information security management system drives the controls that matter here: asset inventory, vulnerability management, secure configuration, access control and supplier security requirements.

Specifically, an ISO 27001 aligned approach helps you to:

• Know where every router lives in your estate (asset management) so you can act fast.
• Require secure default configurations and change control so devices aren’t shipped into production with built‑in keys.
• Operate a vulnerability management process that prioritises critical firmware fixes and records proof of remediation.
• Manage third‑party hardware by contract and assurance, reducing surprises from vendor practices.

And because attackers often cause operational disruption, having tested continuity arrangements matters too — see ISO 22301 business continuity guidance to keep services running while you patch and investigate.

Immediate, practical steps you can take right now

You don’t need to call an emergency board meeting before taking sensible actions. Start with these:

• Identify and inventory: locate every CG3000TC and CG3000T in your estate, in remote offices and supplier networks.
• Patch or replace: apply firmware 1.00.67 (CG3000TC) or 1.00.27 (CG3000T) immediately, or replace devices that cannot be patched.
• Isolate and monitor: put affected routers behind monitoring, restrict administrative access to management VLANs or VPNs, and enable logging to detect suspicious activity.
• Change default/weak configurations: where possible, remove legacy accounts, enforce strong unique credentials and disable unused remote management services.
• Communicate with suppliers: if these devices are part of a supplier’s kit, insist they remediate and provide attestation of fixes.

Longer term: programme‑level actions

Patch now, but build for resilience. Make this a trigger to tighten your baseline defences: network segmentation so an exploited router can’t instantly flatten your internal estate; a formal vulnerability management programme that tracks CVEs to closure; procurement standards that ban devices with insecure defaults; and routine supplier assurance.

Practical frameworks and certifications speed this work. Use Cyber Essentials and IASME to lock down basic configurations, and consider security awareness training via usecure for staff who might need to spot suspicious network behaviour. If you run services that must stay online during incidents, align with ISO 22301 so customers keep being served while you sort the mess.

What governance teams should demand

Boards and risk committees should ask for three things after this disclosure: an inventory and remediation plan for affected devices, evidence that fixes were applied (or devices replaced), and a review of supplier procurement rules to prevent “shipped‑with‑root” devices in the future.

A final, friendly nudge

This vulnerability is a textbook reminder that hardware matters as much as software. Hard‑coded credentials are an avoidable design sin; the fix is simple in principle (patch or replace) but messy in practice if you don’t know where the devices are. If your team treats firmware updates like a polite suggestion, today is the day to change that habit.

Take action: find the routers, patch or isolate them, and use this as the catalyst to shore up your asset inventory, vulnerability management and supplier contracts — and if you want structured help doing that without the drama, ISO 27001 aligned programmes and our support services can turn panic into process.