How to slay a cellphone with a single text

SMS of Death explained


Attacks that crash most older cellphones are frequently compounded by carrier networks that send booby-trapped text messages to the target handset over and over. In other cases, they're aided by a “watchdog” feature embedded in the phone, which takes it offline after receiving just three of the malformed messages.

The so-called SMS of death attacks were unveiled late last year at a hacker conference in Berlin. They use special binary characters and overflowed headers to temporarily crash most older models made by manufacturers including Nokia, Samsung, Sony Ericsson, LG, Motorola, and Micromax. Carrier networks often aggravate the attacks by bombarding the target with the same malicious message, making them an inexpensive way to take a phone completely offline.

“With this bug, you can basically shut down a phone with one SMS and let the network do the retransmission all the time,” Collin Mulliner, a Ph.D. candidate at the Berlin Institute of Technology, told The Reg recently. “For very cheap, you can have the network attack the phone for you.”

The retransmission happens as a result of the way most carrier networks are designed. When they send SMS, or short message service, texts, they cache the message until the phone responds with an acknowledgment indicating it has been properly received. If the answer isn't transmitted, the network will resend the message for hours or days at a time, disabling the phone in the process.

Even in cases when the messages aren't resent, Nokia phones come equipped with a feature dubbed the Watchdog, which is designed to protect a phone by shutting it down after receiving three malformed messages. The SMS causes the Nokia screen to go white and then reboots the phone, causing it to disconnect from the network. Sending the message while a call is in progress will terminate the conversation.

Sending the message three times in close succession invokes the Watchdog to shut down the device. The bug affects virtually all feature phones shipped by Nokia prior to 2010, said Mulliner, who presented updated findings earlier this month at the CanSecWest security conference along with Nico Golde, a Berlin Institute of Technology student who worked on the project for his Master's thesis.

The SMS used to crash Nokia phones was described as an 8-bit class 0 (Flash SMS) with certain TP-UD payload. Messages with different specifications can be used to take out handsets made by other manufacturers.

Feature phones may have lost much of their cachet to smartphones over the past few years, but they are still relied upon by almost 80 percent of the world's mobile phone users, the researchers said.

The attacks could be used in targeted attacks against social enemies and business rivals, but the researchers say there's also the potential for the vulnerabilities to be exploited in a more widespread fashion by using bulk SMS services, smartphone-based botnets, or SS7, a series of telephony signaling protocols the researchers said are becoming increasingly accessible to companies and individuals.

Similar topics


Other stories you might like

  • Robotics and 5G to spur growth of SoC industry – report
    Big OEMs hogging production and COVID causing supply issues

    The system-on-chip (SoC) side of the semiconductor industry is poised for growth between now and 2026, when it's predicted to be worth $6.85 billion, according to an analyst's report. 

    Chances are good that there's an SoC-powered device within arm's reach of you: the tiny integrated circuits contain everything needed for a basic computer, leading to their proliferation in mobile, IoT and smart devices. 

    The report predicting the growth comes from advisory biz Technavio, which looked at a long list of companies in the SoC market. Vendors it analyzed include Apple, Broadcom, Intel, Nvidia, TSMC, Toshiba, and more. The company predicts that much of the growth between now and 2026 will stem primarily from robotics and 5G. 

    Continue reading
  • Deepfake attacks can easily trick live facial recognition systems online
    Plus: Next PyTorch release will support Apple GPUs so devs can train neural networks on their own laptops

    In brief Miscreants can easily steal someone else's identity by tricking live facial recognition software using deepfakes, according to a new report.

    Sensity AI, a startup focused on tackling identity fraud, carried out a series of pretend attacks. Engineers scanned the image of someone from an ID card, and mapped their likeness onto another person's face. Sensity then tested whether they could breach live facial recognition systems by tricking them into believing the pretend attacker is a real user.

    So-called "liveness tests" try to authenticate identities in real-time, relying on images or video streams from cameras like face recognition used to unlock mobile phones, for example. Nine out of ten vendors failed Sensity's live deepfake attacks.

    Continue reading
  • Lonestar plans to put datacenters in the Moon's lava tubes
    How? Founder tells The Register 'Robots… lots of robots'

    Imagine a future where racks of computer servers hum quietly in darkness below the surface of the Moon.

    Here is where some of the most important data is stored, to be left untouched for as long as can be. The idea sounds like something from science-fiction, but one startup that recently emerged from stealth is trying to turn it into a reality. Lonestar Data Holdings has a unique mission unlike any other cloud provider: to build datacenters on the Moon backing up the world's data.

    "It's inconceivable to me that we are keeping our most precious assets, our knowledge and our data, on Earth, where we're setting off bombs and burning things," Christopher Stott, founder and CEO of Lonestar, told The Register. "We need to put our assets in place off our planet, where we can keep it safe."

    Continue reading

Biting the hand that feeds IT © 1998–2022