New IoT Cloud Vulnerability Bypass Firewalls Easily
New IoT Cloud Vulnerability Lets Hackers Bypass Firewalls Easily
A new security study presented ahead of Black Hat Europe 2025 reveals a serious cloud-level weakness affecting millions of IoT devices worldwide. According to the researchers, attackers can silently take over cloud-managed IoT devices — even when those devices sit safely behind firewalls.
This vulnerability does not rely on traditional software bugs. Instead, it targets the way IoT devices authenticate with their vendor’s cloud servers.
Researchers Discover a New IoT Attack Path
Security researcher Jincheng Wang of Nanjing University and independent researcher Nik Xe demonstrated a proof-of-concept attack showing that many IoT devices rely on static identifiers to authenticate with cloud management platforms.
These identifiers include:
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Device serial numbers
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MAC addresses
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Manufacturer-assigned identity patterns
Attackers only need to determine how the cloud platform converts these identifiers into authentication credentials. Once done, they can impersonate the device, access the cloud session, and take over commands that are normally reserved for legitimate administrators.
The Takeover Happens Through the Cloud — Not the Device
The most alarming aspect of this research is that the attacker never needs to directly access the IoT device.
How the attack works:
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IoT device connects to its vendor’s cloud service using a predictable identifier.
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The attacker learns or guesses the identifier (often easily due to predictable patterns).
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The attacker creates a fake device session that competes with the real one.
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Once the cloud server accepts the fake session, the attacker gains control.
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Commands delivered through the cloud appear legitimate and bypass firewalls.
This means:
Cloud management becomes the attacker’s doorway.
Why Serial Numbers & MAC Addresses Are a Weak Link
Many vendors use serial numbers or MAC addresses because they are:
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Easy to generate
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Easy to track
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Already unique
But this simplicity comes at a cost.
Researchers found that serial numbers often follow predictable sequences. MAC addresses reveal the manufacturer ID, which narrows the guessing range. As a result, attackers can brute-force valid identifiers, especially when a cloud platform performs minimal verification.
Once an attacker discovers how the identifier becomes a credential (e.g., hashing, encoding, or concatenation), they can recreate valid login data without ever touching the device.
Why This Is Hard to Detect
This attack vector is extremely stealthy because:
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Commands come from the cloud’s official infrastructure
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Activity resembles normal device traffic
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Vendors rarely log deep cloud-to-device anomalies
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Real device activity may be suppressed by session conflicts
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No malware is installed, leaving almost no traces
Researchers warn that many vendors might silently fix the issue without public disclosure, making real-world attacks difficult to track.
Which Devices Are Potentially Affected?
The study did not name specific brands, but it affects any IoT or network device that:
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Uses cloud-based management
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Authenticates using a static identifier
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Lacks strong mutual validation or device-side cryptography
This includes categories such as:
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Cloud-managed firewalls
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Smart security cameras
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Home routers and mesh systems
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Industrial IoT sensors
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Smart home controllers
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Environmental monitoring systems
Millions of cloud IoT devices operate under this model today.
Industry-Wide Security Problem
The researchers classify this as an architectural weakness, not a traditional CVE-style vulnerability.
That means:
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Many vendors are affected
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Fixing the issue requires a cloud platform redesign
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Legacy devices may never receive an update
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Attackers can exploit this across brands, not just one product line
This is similar to when researchers discovered that default passwords endangered millions of cameras — except this is at the cloud layer, making it potentially much more dangerous.
Recommended Fixes from the Researchers
The study proposes several solutions that vendors should adopt immediately:
Instead of MAC/SN, devices should generate secure random UUIDs during initial provisioning.
If a device connects with a new IP address, the cloud server should trigger re-authentication or an administrator alert.
Vendors should implement cryptographic binding between the device and the cloud, preventing impersonation.
Detailed tracking of duplicate sessions, IP mismatches, or authentication anomalies would help detect attacks.
Until vendors adopt these fixes, the threat remains active.
What This Means for Businesses
Organizations relying on cloud-managed IoT devices should review:
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How their devices authenticate
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Whether identifiers can be predicted
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What monitoring do they have for cloud-to-device traffic
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Whether segmentation or zero-trust controls apply
Companies with large IoT deployments — such as retail chains, factories, logistics, and smart buildings — face the highest exposure.
The new research highlights a dangerous but overlooked threat: your IoT devices can be hijacked through their own cloud platform, even if attackers can’t reach your network.
Because the issue stems from cloud architecture, not firmware bugs, it may take years for the industry to fully resolve. For now, organizations must pressure vendors for stronger authentication and monitor cloud activity more closely.
FAQs-New IoT Cloud Vulnerability Bypasses Firewalls Easily
No. It is an architecture-level weakness in how IoT devices authenticate to cloud services.
In many cases, no — the vendor must update the cloud management platform itself.
Potentially yes, especially cloud-managed cameras and routers.
No. The takeover happens through cloud impersonation.
Moderately. The hardest part is discovering the transformation pattern for identifiers. Once known, exploitation is straightforward.
