Cyber Resilience

CVE-2026-28520

Arduino-Tuyaopen ≤ 1.2.1

Public PoC
Published
16 March 2026
Modified
17 March 2026
Patch / advisory
View advisory
CVSS Score v4 8.6
Click a component to see what it means
Raw vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0019 9th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-28520 is a high-severity Off-by-one Error (CWE-193) vulnerability in Tuya Arduino-Tuyaopen. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-28520 is a single-byte buffer overflow vulnerability (CWE-193) in the WiFiMulti component of the arduino-TuyaOpen library prior to version 1.2.1. This affects embedded smart hardware devices that utilize the library for WiFi connectivity integration with Tuya's IoT platform. The issue, published on 2026-03-16, carries a CVSS v3.1 base score of 8.4 (AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high confidentiality, integrity, and availability impacts.

An attacker can exploit the vulnerability by controlling an access point (AP) hotspot to which the victim's smart hardware connects. No privileges are required (PR:N), and exploitation occurs with low complexity (AC:L) upon connection, allowing the attacker to trigger the buffer overflow and achieve remote code execution on the affected embedded device.

Mitigation involves upgrading to arduino-TuyaOpen version 1.2.1 or later, as indicated by the vulnerability's versioning details. Additional guidance is available in the Tuya announcement at https://src.tuya.com/announcement/32, the project repository at https://github.com/tuya/arduino-TuyaOpen, and the VulnCheck advisory at https://www.vulncheck.com/advisories/arduino-tuyaopen-wifimulti-single-byte-buffer-overflow-remote-code-execution.

EU & UK References

Vulnerability Data

arduino-TuyaOpen before version 1.2.1 contains a single-byte buffer overflow vulnerability in the WiFiMulti component. When the victim's smart hardware connects to an attacker-controlled AP hotspot, the attacker can exploit the overflow to execute arbitrary code on the affected embedded device.

CWE(s)
CWE-193

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-28519Same product: Tuya Arduino-Tuyaopen
CVE-2026-28521Same product: Tuya Arduino-Tuyaopen
CVE-2026-28522Same product: Tuya Arduino-Tuyaopen
CVE-2026-49127Shared CWE-193
CVE-2024-53149Shared CWE-193
CVE-2026-58374Shared CWE-193
CVE-2024-51554Shared CWE-193
CVE-2026-34085Shared CWE-193
CVE-2024-57259Shared CWE-193
CVE-2026-44042Shared CWE-193

Affected Assets

tuya
arduino-tuyaopen
≤ 1.2.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V6.2.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover off-by-one errors in loops, bounds, and calculations before deployment.

SA-15 Development Process, Standards, and Tools partial match

Requiring documented development standards and tools can embed bounds-checking and arithmetic-correctness rules that stop off-by-one mistakes at introduction.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent off-by-one errors via reviews, static analysis, and testing.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development and acceptance can detect off-by-one errors before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle includes requirements and reviews that can catch off-by-one errors.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify bounds-checking and input validation to prevent off-by-one errors.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure system architecture and engineering principles promote defensive coding practices that reduce off-by-one mistakes.

A.8.28 Secure coding partial match
prevents

Secure coding directly addresses off-by-one errors through coding standards and peer review.

References