Anhui Huami Mi Fit Android Application - Unencrypted Update Check
-- 
https://www.info-sec.ca/advisories/Huami-Mi-Fit.html

Overview

"Mi Fit tracks your activity, analyzes sleep, and evaluates your workouts."

(https://play.google.com/store/apps/details?id=com.xiaomi.hm.health)

Issue

The Anhui Huami Mi Fit Android application (version 4.0.10 and below),
does not encrypt the connection when it checks for an update.

Impact

An attacker who can monitor network traffic may be able to tamper with
the application's update function.

Timeline

October 21, 2019 - Attempted to obtain a security contact via an email
to support@amazfit.com
October 22, 2019 - Provided the details to CERT/CC
October 23, 2019 - CERT/CC opened a case for tracking
November 4, 2019 - Attempted to obtain a security contact via an email
to security@xiaomi.com

Solution

Upgrade to version 4.0.11 or later