This Week In Security: Android Malware, VOIP Hijack, Signal Contact Discovery, And TeamPCP Arrests

On GitHub, [AyaanB] details buying a cheap Android TV streaming device, looking for, and finding, baked-in malware.

Multiple warnings have been issued by the FBI and CISA regarding malware on media box Android devices. Many devices have been caught participating in botnets providing residential proxies, ad-click fraud, and DDOS services. [AyaanB] sets out to discover if a $30 set-top streaming box is pre-infected with malware, and extracting it – without ever letting the device talk to the Internet or access other devices on the local network.

Picking a device named in the advisories, [AyaanB] discovered that it was, indeed, preloaded with multiple app stores and applications that wouldn’t typically make sense on a set-top TV box. After identifying the serial port test pads and obtaining a low-voltage serial adapter, they were able to gain access to the bootloader and from there dump the contents of the MMC over TFTP.

With the entire filesystem accessible out-of-body, proving it was infected with malware at the factory becomes simple: the malware is signed as a system application, baked onto the system partition of the MMC, granted SELinux exceptions to mark it as a system binary with shell privileges, and has multiple launch scripts to make sure it is executed even if partially removed. With the malware identified, [AyaanB] continues to dig through to uncover the capabilities.

By installing hooks into the low-level Android process spawning system, the malware installs hooks into every application as it is launched: even if an application isn’t trojaned already, by the time it finishes executing, it’s definitely been subverted. The functions patched and the methods used match the Vo1d botnet, which is used for account takeovers, residential proxies, free “VPN” services, and other unfriendly behavior.

Further digging into the system showed hooks for ad-click fraud, where hidden browser windows are allowed to run unthrottled and display overlays are configured to obscure ads below where the user may click. Other included tools bid in real-time ad auctions, claiming to directly publish ads to the user which may or may not be visible. To cap it all off, a root level backdoor allows botnet operators to access the systems directly and install additional tools.

Be sure to check out [AyaanB]’s writeup for more details on exfiltration methods and other malware found on the devices. Continue reading “This Week In Security: Android Malware, VOIP Hijack, Signal Contact Discovery, And TeamPCP Arrests”

SGX Deprecation Prevents PC Playback Of 4K Blu-ray Discs

This week Techspot reported that DRM-laden Ultra HD Blu-ray Discs won’t play anymore on computers using the latest Intel Core processors. You may have skimmed right past it, but the table on page 51 of the latest 12th Generation Intel Core Processor data sheet (184 page PDF) informs us that the Intel Software Guard Extensions (SGX) have been deprecated. These extensions are required for DRM processing on these discs, hence the problem. The SGX extensions were introduced with the sixth generation of Intel Core Skylake processors in 2015, the same year as Ultra HD Blu-ray, aka 4K Blu-ray. But there have been numerous vulnerabilities discovered in the intervening years. Not only Intel, but AMD has had similar issues as we wrote about in October.

This problem only applies to 4K Blu-ray discs with DRM. Presumably any 4K discs without DRM will still play, and of course you can still play the DRM discs on older Intel processors. Do you have a collection of DRM 4K Blu-ray discs, and if so, do you play them via your computer or a stand-alone player?

RISC-V Will Stop Hackers Dead From Getting Into Your Computer

The greatest hardware hacks of all time were simply the result of finding software keys in memory. The AACS encryption debacle — the 09 F9 key that allowed us to decrypt HD DVDs — was the result of encryption keys just sitting in main memory, where it could be read by any other program. DeCSS, the hack that gave us all access to DVDs was again the result of encryption keys sitting out in the open.

Because encryption doesn’t work if your keys are just sitting out in the open, system designers have come up with ingenious solutions to prevent evil hackers form accessing these keys. One of the best solutions is the hardware enclave, a tiny bit of silicon that protects keys and other bits of information. Apple has an entire line of chips, Intel has hardware extensions, and all of these are black box solutions. They do work, but we have no idea if there are any vulnerabilities. If you can’t study it, it’s just an article of faith that these hardware enclaves will keep working.

Now, there might be another option. RISC-V researchers are busy creating an Open Source hardware enclave. This is an Open Source project to build secure hardware enclaves to store cryptographic keys and other secret information, and they’re doing it in a way that can be accessed and studied. Trust but verify, yes, and that’s why this is the most innovative hardware development in the last decade.

Continue reading “RISC-V Will Stop Hackers Dead From Getting Into Your Computer”