Yes (with caveats)

In todays world, web based exploits are pretty rare. The only time you really see this happen is with full proprietary systems like IPhones because the software stack on those is all intertwined between kernel code and user code, and things like sending a text message with some formatted characters can lead to reboots of phones. But even then, to gain a full command line shell or steal secrets is either impossible due to attack surface, or requires the phone to be in a specific state, like fully factory reset.

The only real danger is chains of trust being compromised, as in some attacker manages to insert malitious code into an already trusted app that uses these exploits.

On a side note i get kick out of reading HN comments about exploitation and hacking. I think people firmly believe that with enough time, a hacker can figure out how to basically take over your phone given any exploit, no matter what it is.

Both mentioned CVEs seem to be about local privilege escalation. So basically yes, if you don't install crap apps, there's a high chance that you are protected. Problem is that it might not seem to be a crap app, but a nice-looking game, etc. Also an attack can come in with an update of any app you have already installed on your phone.

Whilst the play store supposedly scans all apps for malicious behaviour, it's pretty easy to detect the test environment they use for testing and make malicious behaviour only trigger in situations Google doesn't test - eg. 5 days after installation, only if the device IP address changes at least once.

> if I don't install any crap on my phone I am safe?

We don't know. Practically no technical information is released about the bug, for what I care any play store app may exploit this at one time or another and there's no way to know. It's not like everyone and their CFO are shy of exploiting any user data they can get their greedy hands on.