Auth bypass in Espressif Esp8266 Nonos Sdk
CVE-2020-12638
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.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (37.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 37.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/espressif/esp-idf (Third Party Advisory)
- github.com/espressif/ESP8266_NONOS_SDK (Third Party Advisory)
- github.com/espressif/ESP8266_RTOS_SDK (Third Party Advisory)
- lbsfilm.at/blog/wpa2-authenticationmode-downgrade-in-espressif-microprocessors (Exploit, Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-12638?
- CVE-2020-12638 is a medium-severity vulnerability in Espressif Esp8266 Nonos Sdk, classified under Improper Authentication. CVSS score: 6.8/10. Published 2020-07-23.
- How severe is CVE-2020-12638?
- Medium severity. CVSS v3 base score is 6.8 out of 10.