What are the security disadvantages of rooting an Android phone? I know there was a discussion previously BUT they didn't talk about security. E.g.: if I root my phone will all my apps run with root permission?

Related: Are there any risks to rooting a device?
If you root your phone, then only the applications that you explicitly grant root access to will have root access.  This does make things fairly safe, as that extra step should be enough to make you stop and think "Why does this app need root?".

If you only grant root access to apps that need root for a good reason, are from trusted developers, and which you acquired from a trusted source then you should be ok.

Bear in mind what apps with root access can do though - from a previous answer on the subject:


  On a rooted phone, an app which has been granted root access can do pretty much anything  that is possible in the hardware. Apps that have root permissions can write on non-read-only storage media (including modifying the bootloader), modify other programs' private data, modify system settings, modify system files, etc. A rooted app can also hide itself from the system, and pretend to be uninstalled while being perfectly well and alive.


I'll let you imagine what the worst-case scenario security implications are for a nefarious app being granted root access on your phone; be careful out there.