CVE-2020-12638: Espressif Esp-Idf

Medium severity, CVSS 6.8. EPSS: 0.5% chance of exploitation in the next 30 days.

An encryption-bypass issue was discovered on Espressif ESP-IDF devices through 4.2, ESP8266_NONOS_SDK devices through 3.0.3, and ESP8266_RTOS_SDK devices through 3.3. Broadcasting forged beacon frames forces a device to change its authentication mode to OPEN, effectively disabling its 802.11 encryption.

Affected products

• Espressif Esp-Idf: up to and including 4.2
• Espressif ESP8266 Nonos SDK: up to and including 3.0.3
• Espressif ESP8266 Rtos SDK: up to and including 3.3

Published 2020-07-23. Last modified 2026-06-17.