Protecting Android users from 0-Day attacks

To protect our users, Google’s Threat Analysis Group (TAG) routinely hunts for 0-day vulnerabilities exploited in-the-wild. In 2021, we reported nine 0-days affecting Chrome, Android, Apple and Microsoft, leading to patches to protect users from these attacks.

This blog is a follow up to our July 2021 post on four 0-day vulnerabilities we discovered in 2021, and details campaigns targeting Android users with five distinct 0-day vulnerabilities:

We assess with high confidence that these exploits were packaged by a single commercial surveillance company, Cytrox, and sold to different government-backed actors who used them in at least the three campaigns discussed below. Consistent with findings from CitizenLab, we assess government-backed actors purchasing these exploits are located (at least) in Egypt, Armenia, Greece, Madagascar, Côte d’Ivoire, Serbia, Spain and Indonesia.

The 0-day exploits were used alongside n-day exploits as the developers took advantage of the time difference between when some critical bugs were patched but not flagged as security issues and when these patches were fully deployed across the Android ecosystem. Our findings underscore the extent to which commercial surveillance vendors have proliferated capabilities historically only used by governments with the technical expertise to develop and operationalize exploits.

Seven of the nine 0-days TAG discovered in 2021 fall into this category: developed by commercial providers and sold to and used by government-backed actors. TAG is actively tracking more than 30 vendors with varying levels of sophistication and public exposure selling exploits or surveillance capabilities to government-backed actors.


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