Google’s Project Zero has warned that it suspects an Android zero-day flaw actively is being exploited by the controversial Israeli-based NSO Group Technologies or one of its customers. The NSO Group has been criticised for selling zero-day exploits to “authorised governments”.
The vulnerability was found in the kernel of the Android operating system and can be utilised by an attacker to gain root access to a device.
Project Zero member Maddie Stone wrote Thursday that there are indicators that the exploit is “allegedly being used or sold by the NSO Group. The NSO Group has publicly denied having anything to do with the exploit, including selling it.
Stone said the unpatched vulnerability (CVE-2019-2215) can be exploited in several ways. In one scenario, a target is enticed to download a rogue app. The second method of infection includes chaining the bug with an additional vulnerability in code the Chrome browser uses to render content.
“It is a kernel privilege escalation [bug] using a use-after free vulnerability, accessible from inside the Chrome sandbox,”
“The vulnerability is exploitable in Chrome’s renderer processes under Android’s ‘isolated_app’ SELinux domain, leading to us suspecting Binder as the vulnerable component.”
A patch for the vulnerability is expected in the next few days as part of Google’s October Android security update.
Strangely enough, the vulnerability was patched back in December of 2017 in Android kernel versions 3.18, 4.14, 4.4 and 4.9, though newer versions of Android were found to be vulnerable.
According to Google’s researchers, the vulnerability impacts the Pixel 2, Huawei P20, Xiaomi Redmi 5A, Xiaomi Redmi Note 5, Xiaomi A1, Oppo A3, Moto Z3, LG phones running Oreo and the Samsung S7, S8 and S9 running Android version 8 or higher.
However, since the “exploit requires little or no per-device customisation”, this means that it may impact even more Android smartphones but those listed above have been tested and confirmed to be vulnerable to the zero-day by Google.
While Google’s Project Zero team first discovered the vulnerability, the company’s Threat Analysis Group (TAG) confirmed that it had been used in real-world attacks. Both of these teams were also responsible for discovering a recent batch of zero-day vulnerabilities in Apple’s iPhones.