CVE-2026-28522 identifies a null pointer dereference vulnerability in the WiFiUDP component of the arduino-TuyaOpen library, versions prior to 1.2.1. The flaw arises when an attacker on the same local area network floods the target device with a high volume of malicious UDP packets. This flood leads to memory exhaustion, which subsequently triggers a null pointer dereference error within the WiFiUDP handling code. The consequence is a denial-of-service condition that can crash or severely disrupt the affected device’s operation. The vulnerability requires no authentication or user interaction, making it accessible to any attacker with local network access. The arduino-TuyaOpen library is a popular open-source framework used to integrate Tuya IoT devices with Arduino platforms, commonly found in smart home devices, industrial sensors, and other connected embedded systems. The CVSS 4.0 base score of 7.1 reflects the high impact on availability and the low complexity of attack execution. Although no public exploits have been reported yet, the vulnerability’s nature suggests it could be weaponized to disrupt IoT deployments, causing service outages and potential operational impacts. The lack of patch links indicates that users should monitor vendor updates closely and consider interim mitigations.

The primary impact of this vulnerability is denial-of-service on IoT devices using the vulnerable arduino-TuyaOpen library. This can lead to device crashes or unresponsiveness, disrupting smart home automation, industrial monitoring, or other critical IoT functions. Organizations relying on these devices may experience operational downtime, reduced service availability, and potential safety risks if critical sensors or actuators become unavailable. The attack requires local network access, so environments with open or poorly segmented networks are at higher risk. The vulnerability could be exploited to cause widespread disruption in environments with many affected devices, such as smart buildings, manufacturing plants, or large-scale IoT deployments. While confidentiality and integrity are not directly impacted, the availability loss can have cascading effects on business continuity and user trust.

To mitigate this vulnerability, organizations should upgrade arduino-TuyaOpen to version 1.2.1 or later once available. Until patches are released, network segmentation should be enforced to restrict local network access to trusted devices only. Implementing strict firewall rules to block unsolicited UDP traffic to IoT devices can reduce exposure. Monitoring network traffic for unusual UDP floods can help detect attempted exploitation. Device hardening by disabling unnecessary UDP services or limiting UDP packet rates may also mitigate risk. Additionally, deploying intrusion detection systems (IDS) tuned for UDP flood patterns can provide early warning. Vendors and integrators should prioritize firmware updates and communicate with end users about the importance of patching. For critical environments, consider isolating vulnerable devices on separate VLANs or air-gapped networks to prevent local attacker access.