Security researchers found vulnerabilities in the Qualcomm TrustZone secure element extension that could allow attackers to steal the most sensitive data stored on mobile devices.
TrustZone implements architectural security extensions on ARM processors that can be integrated into the bootloader, radio, Android system image and a trusted execution environment (TEE) in mobile devices. Slava Makkaveev, security researcher at Check Point Software Technologies, discovered the issues in the Qualcomm TrustZone implementation often used by major Android manufacturers.
“TEE code is highly critical to bugs because it protects the safety of critical data and has high execution permissions. A vulnerability in a component of TEE may lead to leakage of protected data, device rooting, bootloader unlocking, execution of undetectable APT and more. Therefore, a Normal world OS restricts access to TEE components to a minimal set of processes,” Makkaveev wrote in his analysis. “Examples of privileged OS components are DRM service, media service and keystore. However, this does not reduce researchers’ attention to the TrustZone.”
Makkaveev said the Qualcomm TrustZone components can be found in popular Android devices from Samsung, Google, LG and OnePlus. He used fuzzing tools to discover the vulnerabilities and exploited them in order to install a trusted app in a normal environment.
Check Point claimed the flaws affect all versions of Android up to the most recent Android 10; however, Makkaveev mentions testing on only a Nexus 6 running Android 7.1, an LG G4 running Android 6 and Moto G4/G4 Plus running an unknown version of Android.
Samsung, Motorola, LG and Qualcomm did not respond to requests for comment at the time of this post. Google responded but did not have information readily available as to whether more recent Google Pixel devices are at risk.
Liviu Arsene, global cybersecurity researcher at antimalware firm Bitdefender, based in Romania, told SearchSecurity this research is important because “high-complexity and high-reward vulnerabilities [like this] can potentially offer untethered access to critical assets and data on the device.”
“When a vulnerability in the software that sits between the hardware and the operating system running on top of it is found, successful exploitation can have serious security and privacy implications,” Arsene said. “Not because attackers could potentially access critical and sensitive data, but because attackers can compromise the security of the device, while being invisible to the victim. Depending on how the vulnerability is triggered, weaponized attackers might successfully exfiltrate sensitive data such as passwords, financial information, or even planting additional software on the device.”
Ekram Ahmed, head of public relations at Check Point, told SearchSecurity, “it’s only a matter of time before we find more vulnerabilities.”
Ekram AhmedHead of public relations, Check Point
“Once someone gains access into Trust Zone, it’s game over. They can get unprecedented access to our credit cards, biometric data, keys, passwords,” Ahmed said. “It wouldn’t be too difficult for a medium-skilled cyber actor to exploit. What is difficult is knowing exactly who is affected. The vulnerability is a deeper infrastructure issue.”
Arsene said he wouldn’t expect to see these Qualcomm TrustZone flaws exploited “en masse in the wild.”
“While weaponizing the vulnerability may be possible, it’s likely that only a handful of users could potentially be impacted, possibly in highly targeted attacks,” Arsene said. “However, the difficulty of pulling off these attacks lies in how easily the vulnerability can be weaponized.”
Ahmed added that Check Point notified all potentially affected device manufacturers, but the company had “strange” interactions with Qualcomm leading up to the patch being released.
“We asked them to patch, and they only told us they patched a day before we published the blog, because the media was reaching out to them,” Ahmed said. “They went months without communicating a single word to us.”