BadBox rapidly grows, 190,000 Android devices infected

Experts uncovered a botnet of 190,000 Android devices infected by BadBox bot, primarily Yandex smart TVs and Hisense smartphones.

Bitsight researchers uncovered new BADBOX infrastructure, company’s telemetry shows that over 192,000 devices were infected with the BADBOX bot.

The botnet includes 160,000 previously unseen devices, notably Yandex 4K QLED Smart TVs and T963 Hisense Smartphones. Most of the infected devices are in Russia, China, India, Belarus, Brazil and Ukraine

Bitsight sinkholed a BADBOX domain, logging over 160,000 unique IPs in 24 hours, with the number tha continues to increase.

BADBOX-infected devices send telemetry to a C2 server upon boot, awaiting instructions.

“The coslogdydy[.]in url received several communications matching that of BADBOX” reads the Bitsight’s report. “This quickly indicated two things: First, the models ranging from YNDX-00091 to YNDX-000102 are 4K Smart TVs from a well-known brand, not cheap Android TV boxes. It’s the first time a major brand Smart TV is seen directly communicating at such volume with a BADBOX command and control (C2) domain, broadening the scope of affected devices beyond Android TV boxes, tablets, and smartphones.” continues the report “Second, let’s talk volume. Telemetry collected indicates that more than 160,000 unique IPs communicate daily, a number that has been steadily growing.”

Recently, The Federal Office for Information Security (BSI) announced it had blocked communication between the 30,000 devices infected with the BadBox malware and the C2. The devices were all located in Germany, they were all using outdated Android versions.

Technically authorities sinkholed the botnet, an operation that involves redirecting the traffic from infected devices, which would normally communicate with the attacker’s C2 server, to a controlled server or “sinkhole” managed by security researchers or law enforcement. Sinkholing isolates the malware and prevents it from executing commands or stealing data.

The BadBox malware, pre-installed on devices, creates email and messaging accounts for spreading disinformation. The bot conducts ad fraud by accessing websites in the background and operates as a residential proxy, sharing the user’s internet connection for criminal activities, which can link the user’s IP address illegal activities. BadBox can also download additional payloads, amplifying the risks for the users.

The BSI instructed all internet providers in the country with more than 100,000 subscribers to help it to carry out sinkholing operations.

In October 2023, cybersecurity researchers at Human Security discovered a global network of consumer products, dubbed BADBOX, with firmware backdoors installed and sold through a compromised hardware supply chain.

The experts reported that at least 74,000 Android-based mobile phones, tablets, and Connected TV boxes worldwide were shipped with the backdoored firmware.

Products containing the malicious backdoor have been found on public school networks throughout the United States.

Unfortunately, the BSI’s recent operation had a limited impact on BadBox operation, as the law enforcement action was limited to the country.

“The BADBOX operation showcases how cyber criminals are further mastering the art of using global supply chains to spread their malware far and wide.” concludes the report. “While this blog post focused on infected devices with higher density in Russia and China, BADBOX malware is an epidemic affecting all countries and most types of android devices.”

Follow me on Twitter: @securityaffairs and Facebook and Mastodon

Pierluigi Paganini

(SecurityAffairs – hacking, botnet)