The Raspberry Pi is not as secure as you might have thought.
It’s been a year already, for security researchers uncovering groundbreaking research of the hacker variety. What with the iPhone USB-C controller hack and news of an emerging threat to 100 million macOS users, to name just two examples. Now you can add a third: a hack that bypasses high-security protection measures with the potential to extract confidential secrets, including encryption keys, from a Raspberry Pi. Here’s what you need to know and why you shouldn’t worry too much just yet.
Exclusive: Raspberry Pi RP2350 Microcontroller Hack
Security researchers from IOActive accepted the challenge set by the Raspberry Pi at the DEF CON 2024 hacking convention to bypass the signed boot process present in the A2 revision of the RP2350 microcontroller, an ARM Cortex-M33 and Hazard3 RISC-V dual 32- very safe bit. integrated circuit, to allow the execution of unsigned code and, using that access, to read the secrets from the one-time programmable memory on the chip. That challenge ran from August 8 to December 31, 2024, but details of a successful hack have only been released today. Here are the exclusive details from IOActive.
Dr. Andrew Zonenberg, a principal consultant at IOActive led the research team of Antony Moor, Daniel Slone, Lain Agan and Mario Cop, and said they “found a very unique attack vector for reading data from antifuse memory, which we internalized for to develop further.” In a stark reminder of the seriousness of this research, Zonenberg concluded: Those who rely on antifuse memory for confidentiality should immediately reevaluate their security posture.
The fact that the IOActive research team has demonstrated the ability to extract the contents of the antifuse bit cells in the Raspberry Pi RP2350 microcontroller via a physical invasive attack is not a good thing. The RP2350 uses a disposable Synopsys antifuse memory block for storing secure boot keys and other sensitive configuration data. Synposis describes the antifuse-based solution as a “proven, reliable and secure technology that is widely adopted and used in a wide range of applications and markets.”
“We are impressed with the work IOActive has done to extract secrets directly from programmable memory once against fuses in our microcontroller products,” said Eben Upton, CEO at Raspberry Pi, “This is an innovative approach that is likely affect a Many products on the market Responsive disclosure of these types of vulnerabilities helps semiconductor vendors like us build more secure products over time.”
The Raspberry Pi RP2350 Compromise—A Very Expensive Hack
Here’s the real-world vs. labs part of the full attack methodology that leaves me thinking that this Raspberry Pi hack is unlikely to affect users just yet. The attacker would have to have physical possession of an RP2350 device, that’s a given, but the research team also confirmed that they would need “access to semiconductor processing equipment and a focused ion beam system to extract the contents of antifuse bit cells as plain text in a few days.” Which sounds kind of nervous and scary at the same time. However, the researchers acknowledged that a FIB system is “a very expensive scientific instrument that costs several hundred thousand dollars with operating expenses in the tens of thousands per year.”
But wait, that doesn’t mean this is just some kind of fantasy adventure. Such a kit can be rented from a university lab for several hundred dollars per hour, which is worth considering when considering the immediate real-world impacts. The researchers noted that “this is low enough to be within the realm of feasibility in many scenarios given the potential value of the keys on the device.” Indeed, in theory, the attack could be pulled off using a single device and within weeks of uptime for a skilled hacker to “perform the initial reverse engineering and process development on blank or programmed test chips the attacker”. Current target devices would take another day or two per chip to sample and extract a small amount of data like a key, with a full fuse bank requiring an extra day of machine time to the image of the whole group, the report says.
Raspberry Pi Hack means you need to reassess the risk of your confidential data, warned IOActive
“The fully invasive antifuse memory reading technique we demonstrated with the RP2350 example could potentially be used against other types of antifuse memory,” IOActive’s senior vice president of research and strategy John Sheehy told me, “which are often used to stored. small amounts of data that change infrequently and may include sensitive data that requires confidentiality such as shared cryptography or private keys.”
Anyone using anitfuse-based drives to store confidential data should reassess their risks from this new attack vector, Sheehy warned, adding that “those who assumed it was extremely difficult or impossible to read the data of antifuse-based memories are likely to be at significant risk for this type of attack.”
Sheehy said that, based on the current maturity of the IOActive hacking technique, he estimated that users of these products could act to make this attack much more costly and therefore less likely to be executed by adjusting how how they write sensitive data to these types of antifuse – based memories. “We detail our overall recommendation on this in the full disclosure report,” Sheehy said, concluding, “We’ve been in communication with Raspberry Pi, and they’ve been extremely responsive and professional about the disclosure.”
I have contacted Sinopsis for a statement regarding the Raspberry Pi RP2350 antifuse memory hack.
