CVE-2026-28519
📋 TL;DR
A heap-based buffer overflow vulnerability in the DnsServer component of arduino-TuyaOpen allows attackers on the same local network to send malicious DNS responses, potentially leading to arbitrary code execution on affected embedded devices. This affects users of arduino-TuyaOpen library versions before 1.2.1 in IoT/embedded projects.
💻 Affected Systems
- arduino-TuyaOpen library
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full remote code execution with device compromise, allowing attacker persistence, data theft, or device takeover
Likely Case
Device crash/DoS or limited code execution depending on exploit reliability and memory protections
If Mitigated
Denial of service if ASLR/stack protections prevent reliable RCE
🎯 Exploit Status
Requires attacker to control or spoof LAN DNS server responses; exploit reliability depends on target memory layout
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.2.1
Vendor Advisory: https://src.tuya.com/announcement/32
Restart Required: Yes
Instructions:
1. Update arduino-TuyaOpen library to version 1.2.1 or later via Arduino Library Manager or manual installation. 2. Recompile and redeploy affected embedded applications. 3. Restart devices running patched firmware.
🔧 Temporary Workarounds
Disable DnsServer component
allRemove or disable DnsServer functionality if not required
Modify source code to remove DnsServer initialization and usage
Network segmentation
allIsolate IoT devices on separate VLAN from untrusted systems
🧯 If You Can't Patch
- Segment IoT devices on isolated network VLAN with strict firewall rules
- Implement network monitoring for DNS response anomalies and block malicious DNS servers
🔍 How to Verify
Check if Vulnerable:
Check arduino-TuyaOpen library version in Arduino IDE or project dependenciesCheck Version:
Check Arduino library manager or inspect library.properties file for versionVerify Fix Applied:
Confirm library version is 1.2.1 or later and DnsServer component has proper bounds checking📡 Detection & Monitoring
Log Indicators:
- Device crashes/restarts
- Memory corruption errors in system logs
- Unusual DNS query patterns
Network Indicators:
- Malformed DNS responses to IoT devices
- DNS traffic from unauthorized servers
SIEM Query:
dns.response AND (device_type:iot OR device_vendor:tuya) AND dns.response.size > threshold