[Q] security of rooting apps and custom roms

Customizing and rooting one's phone can be done very securely. Even more now than a few years ago. I would be wary about apps that can root your phone with a buttoon press. Unless, of course, there is a really long thread about it on xda. The same with apps not from the Google store. You should run a virus scan on any apks you get in general. They can contain malicious code that can mess up your device and steal your information.

Once you root your device, it's a good idea to look into the XPrivacy app. You can use it to control the individual permissions of all of your installed app. There are a lot of other security measure you can take too. Do research on what would be relevant to your device.

kbntk said:

Hello,

I think about rooting my device.
However I also think about how secure the custom roms builds or rooting apps are.

E.g.
In the modaco forum there is a tool called Superboot r2 to root the motorola moto g device.
How can I know/trust that this tool doesn't contain any spyware/malware or other malicous code?

How do you guys look at the security of custom roms and other apps which root your device?

Click to expand...

Click to collapse

Rooting a device greatly decreased the overall security of the device. You are breaking the basic security design of Android, you are incorporating new code (mods etc) from developers who may not be properly trained, many who jsut copy past code from elsewhere without understanding what exactly is going on. Potentially (almost certainly with most custom roms) introducing new vulnerabilities.

Elzbach said:

Customizing and rooting one's phone can be done very securely. Even more now than a few years ago. I would be wary about apps that can root your phone with a buttoon press. Unless, of course, there is a really long thread about it on xda. The same with apps not from the Google store. You should run a virus scan on any apks you get in general. They can contain malicious code that can mess up your device and steal your information.

Once you root your device, it's a good idea to look into the XPrivacy app. You can use it to control the individual permissions of all of your installed app. There are a lot of other security measure you can take too. Do research on what would be relevant to your device.

Click to expand...

Click to collapse

I'm going to have to flat out disagree. Once you have rooted your device, security has greatly been decreased. What would be a minor vulnerability in a normal app, can become a huge vulnerability in an application that has been granted permission to use root. Same goes for the Superuser control application.

kbntk said:

Thank you for your replies guys.



I agree rooding the device decreases the overall secruity of the device.
On the other hand, rooting the device gives access to the apps that give you control over the system and data on it. For example as Elzbach wrote, with the app XPrivacy I can control what apps have access to my personal information.
Now - without root - when I instal a new keyboard or launcher with widgets, I'm warned that these apps can have access to my personal information and can use them malicously. For me that means, that even without root using normal apps I can get big security risk when using some apps from play store.

Do you build the custom android version by yourself from the source or use builds provided on this forum or modaco or use another way?

Click to expand...

Click to collapse

XPrivacy, and apps like them introduce additional security concerns of their own. Android is not designed to work the way they force it too, introducing many new unknowns.

New keyboard, launchers introduce an infinitely smaller risk than any root app, and unlike with root apps you are warned and privileges are handled by an established well tested permission system. Comparing the two is completely silly.

Any developer, in a matter of minutes, put together a root app requesting 0 permissions, that can gain permissions or otherwise use APIs requiring permissions at runtime without declaring them, and disable or work around any "security" any XPrivacy type app claims to provide. Once rooted, apps like XPrivacy provide a complete false sense of security. Given you need root to use them... they provide no real security at all.

A completely valid scenario (one we have seen in the wild): An app with 0 permissions, but the ability to use su could download and dynamically execute new code to perform the malicious activities. IE Google bouncer, and any anti virus software would be @#$@ out of luck on that one. All because a user decided to completely break the basic security model, by installing su.

The only customized version of Android I use, is a customized emulator I use for analysis, and that only used when I suspect something could damage an actual test device.

I do not mess with customized versions of Android on real hardware, I only build when testing patches I plan to push to the AOSP gerrit for review.

jcase said:

Rooting a device greatly decreased the overall security of the device. You are breaking the basic security design of Android, you are incorporating new code (mods etc) from developers who may not be properly trained, many who jsut copy past code from elsewhere without understanding what exactly is going on. Potentially (almost certainly with most custom roms) introducing new vulnerabilities.




I'm going to have to flat out disagree. Once you have rooted your device, security has greatly been decreased. What would be a minor vulnerability in a normal app, can become a huge vulnerability in an application that has been granted permission to use root. Same goes for the Superuser control application.

Click to expand...

Click to collapse

jcase said:

XPrivacy, and apps like them introduce additional security concerns of their own. Android is not designed to work the way they force it too, introducing many new unknowns.

New keyboard, launchers introduce an infinitely smaller risk than any root app, and unlike with root apps you are warned and privileges are handled by an established well tested permission system. Comparing the two is completely silly.

Any developer, in a matter of minutes, put together a root app requesting 0 permissions, that can gain permissions or otherwise use APIs requiring permissions at runtime without declaring them, and disable or work around any "security" any XPrivacy type app claims to provide. Once rooted, apps like XPrivacy provide a complete false sense of security. Given you need root to use them... they provide no real security at all.

A completely valid scenario (one we have seen in the wild): An app with 0 permissions, but the ability to use su could download and dynamically execute new code to perform the malicious activities. IE Google bouncer, and any anti virus software would be @#$@ out of luck on that one. All because a user decided to completely break the basic security model, by installing su.

The only customized version of Android I use, is a customized emulator I use for analysis, and that only used when I suspect something could damage an actual test device.

I do not mess with customized versions of Android on real hardware, I only build when testing patches I plan to push to the AOSP gerrit for review.

Click to expand...

Click to collapse

Well I stand corrected.

Apologize if I'm resurrecting an oldie but this is a topic I've been contemplating for a while now. I used to root, looking back to my old OG Droid days. But I find newer devices sufficient as to not root anymore (mostly). I'm currently debating rooting a Samsung Tab S 8.4 to remove Touchwiz and hopefully speed some things up and maybe further control the CPU.

If the user is rooted and they only install apps from the marketplace that are known to be safe (I assume)- i.e.- not downloaded from some misc internet site and from "non-trusted sources," would this still be able to happen?
- "Any developer, in a matter of minutes, put together a root app requesting 0 permissions, that can gain permissions or otherwise use APIs requiring permissions at runtime without declaring them, and disable or work around any "security" any XPrivacy type app claims to provide. Once rooted, apps like XPrivacy provide a complete false sense of security. Given you need root to use them... they provide no real security at all."

I guess I'm just not sure how google approved apps, or if they even do. And what's the process of showing app permissions in the Play Store these days, since permissions are front and center when you download an app. Do dev's just flag permissions on their own will or is it built into the Android code? I would ASSUME the android code when posting to Play Store decides permissions for the dev. I would be horrified if Android relied on good will for people to post permissions solely from the dev's input.

I could be completely wrong
But as I understand dev a pick the permissions they need for the app to work correctly. They declare the permissions they need to the Android system. And then they can only use those permissions and no others. However they don't need to use all of the permissions but they can if they want to.

Btw apps from google play are in no way safe.it has no bearing if you do or don't have apps from unknown sources on your device. fact is google in no way checks the source code of apps on the play store.now maybe the run a virus checks but honestly that means nothing as moron could code in malicious code that would not trigger a scanner (and Trojans are far more prevalent for Android than viruses). If the source code is not available then no one knows what an app could be doing.

90% of my apps come from fdroid, who builds everything from source.

In the discussion above I should also note (but could be wrong about this completely) that system apps (the ones that come with your phone) all have root(administrator) permissions by virtue of being system components.
So rooting may decrease your security but personally I think factory roms are far too unsecure to start with and will never have a device that is not rooted. The benefits far out weight the risks for the careful user. Until such time as the source code is released.

Unless you trust google, face book, Samsung, Twitter, and a host of other baked in developers who get to put apps on your phone at the factory.
Or Apple who has their own way of making money off your every move, or microsoft with win 10 that also sells your habits.

jcase said:

Rooting a device greatly decreased the overall security of the device. You are breaking the basic security design of Android, you are incorporating new code (mods etc) from developers who may not be properly trained, many who jsut copy past code from elsewhere without understanding what exactly is going on. Potentially (almost certainly with most custom roms) introducing new vulnerabilities.




I'm going to have to flat out disagree. Once you have rooted your device, security has greatly been decreased. What would be a minor vulnerability in a normal app, can become a huge vulnerability in an application that has been granted permission to use root. Same goes for the Superuser control application.

Click to expand...

Click to collapse

This alone is enough for me to stay away from root and its capability to make things worse in my end. Thank you for the professional input on this.

Without root you can't add any security to Android. Which has very little security to start with. Permissions are vague and can't be denied on a per app basis short of not installing the app.
System apps have no way of being removed without root unless you do it before flashing, and without root you can't do a complete backup of your system.

Even if you don't root a device yourself Trojans can gain root with many of the same exploits, root themselves and cause whatever havoc they desire.

An app only gets root if you allow it even after rooting your device. It will pop up and ask you if you want to allow or deny or always allow or deny. a Trojan that can create root will do can do it regardless if you root your device yourself, I have no idea if such a Trojan tried to get root if supersu, or superuser will pop up and ask.

A firewall requires root and that alone is worth rooting for me.
But then I have very few apps that I allow online.

Can root cause serious damage to your device? Yes
Can you administrator your device without root? No
Every Linux has root capabilities,
if you own it you should be able to administer it to the best of your abilities and to do that you need root.

Custom Roms are updated far more often that oem roms and as such generally have the newest fixes and updates for security.come that to factory roms that may update once or twice in their expected lifetime, regardless of how many security holes are found in the rom.older devices(read older as a synonym for 2 years old) may never get another update and the only way to protect yourself with out a custom Rom is to buy a new device.

For example Android 5.01 has a major memory leak.and even with that and other bugs and security issues Samsung had not updated the north American galaxy s5 (just over a year old,) above 5.01 yet and may not until marshmallow comes out (Which will mean almost a year after the security and memory leak were found). And until then you walk around using a device with major security issues and a major memory leak.

XPrivacy is not about Security. "Security" is never linked to Xprivacy on Github. "XPrivacy can prevent applications from leaking privacy-sensitive data". Saying the opposite is a lie.
Whether you have root access or not you can almost do nothing against serious attacks BUT having root access allows you to control some things like Internet connection, restricted access,...
Finally do not confuse Custom ROMs and Root. You can run a custom rom without root and vice versa. As explained above custom ROMs are more updated so you can enjoy more patches and new security features like SElinux.

Kayak83 said:

Apologize if I'm resurrecting an oldie but this is a topic I've been contemplating for a while now. I used to root, looking back to my old OG Droid days. But I find newer devices sufficient as to not root anymore (mostly). I'm currently debating rooting a Samsung Tab S 8.4 to remove Touchwiz and hopefully speed some things up and maybe further control the CPU.

If the user is rooted and they only install apps from the marketplace that are known to be safe (I assume)- i.e.- not downloaded from some misc internet site and from "non-trusted sources," would this still be able to happen?
- "Any developer, in a matter of minutes, put together a root app requesting 0 permissions, that can gain permissions or otherwise use APIs requiring permissions at runtime without declaring them, and disable or work around any "security" any XPrivacy type app claims to provide. Once rooted, apps like XPrivacy provide a complete false sense of security. Given you need root to use them... they provide no real security at all."

I guess I'm just not sure how google approved apps, or if they even do. And what's the process of showing app permissions in the Play Store these days, since permissions are front and center when you download an app. Do dev's just flag permissions on their own will or is it built into the Android code? I would ASSUME the android code when posting to Play Store decides permissions for the dev. I would be horrified if Android relied on good will for people to post permissions solely from the dev's input.

Click to expand...

Click to collapse

Go to F-Droid or fossdroid instead of Google Play to avoid crappy apps and unwanted connections. Apps on F-Droid are safer. Google has an automatic system to scan apks when they are uploaded but it doesn't detect everything... Be sure that if you didn't update the version number of your apk you will be blocked though lol
Permissions are stored in the AndroidManifest.xml. If the developer doesn't want to state the permissions he needs then nothing will be shown into the Manifest. That's why it's important to use 3rd party apps to control what apps really do.

Would never use my phone without a firewall installed. I want to have control over what apps can access the net and which cannot.
So rooting is a must for me.
Have no gapps installed and privacy is important to me.

Semseddin said:

This alone is enough for me to stay away from root and its capability to make things worse in my end. Thank you for the professional input on this.

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Click to collapse

And you'll be 100% wrong. You are getting a bad advice from someone who sounds like he works for Google. He is wrong and he knows it...

Your system apps have root whether you like it or not. So, they can do whatever Google wants them to do. And they can do it silently. So, the question is are you going to have control over your device or google? Without root you can't; with root you can if you know what you are doing. Your main security threat comes from Gapps and the infamous google services framework, which spies on you and regularly transmits home (google servers) your every activity. That has to go and for that you need root. Custom rom vs stock. Custom roms don't have Gapps and gsf, so that puts them on pedestal, as compared to stock. Stock rom is android plus manufacturer's bloat which also spies on you and wastes battery. Custom roms don't have gapps and they are open source (like Linux). Have you ever heard about viruses on Linux? Maybe 2 or 3, but thousands in other OSs. As another user noted, linux (on which android is based) has root. So is any major OS. Root is just a key to control your device. It can be set up to restrict everything, even system apps, so the point that having root reduces security is invalid except for one situation, when you don't know what you are doing. Do you want incompetent and malicious evil Google to own your phone? If you do, stay away from root.

optimumpro said:

And you'll be 100% wrong. You are getting a bad advice from someone who sounds like he works for Google. He is wrong and he probably knows it...

Your system apps have root whether you like it or not. So, they can do whatever Google wants them to do with your device. And they can do it silently. So, the question is are you going to have control over your device or google? Without root you can't; with root you can if you know what you are doing. Your main security threat comes from Gapps and the infamous google services framework, which spies on you and regularly tramsmits home (google servers) your every activity. That has to go and for that you need root. Custom rom vs stock. Custom roms don't have Gapps and gsf, so that puts them on pedestal, as compared to stock. Stock rom is android plus manufacturer's bloat which also spies on you and wastes battery. Custom roms don't have gapps and they are open source (like Linux). Have you ever heard about viruses on Linux? Maybe 2 or 3, but thousands in other OSs. As another user noted, linux (on which android is based) has root. So is any major OS. Root is just a key to control your device. It can be set up to restrict everything, even system apps, so the point that having root reduces security is invalid except for one situation, when you don't know what you are doing. Do you want incompetent and malicious evil Google to own your phone? If you do, stay away from root.

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Click to collapse

Thank you for your detailed answer but if i am not mistaken, are you suggesting that a custom rom made by a 3rd party hobbiest developer is more secure than oem's firmware ? If so, i will continue to be mistaken.

Semseddin said:

Thank you for your detailed answer but if i am not mistaken, are you suggesting that a custom rom made by a 3rd party hobbiest developer is more secure than oem's firmware ? If so, i will continue to be mistaken.

Click to expand...

Click to collapse

Most of the time the answer is yes. Also, you could be a developer yourself meaning you can compile your rom from sources with your own modifications. OEMs have user's security on the back burner. Their goal is to monetize the user and in case of mobile devices, there is no way to monetize the user without compromising security. The beauty of a published source code is that anyone could examine it and they do (even if it is not you yourself). Look at businesses: the majority of them use neither windows nor apple. They use Linux, because linux does not monetize the user and it is open sources and by the way, it is maintained by "hobbiest" developers. And naturally, because of this Linux has a vastly superior security and virtually no viruses.

Google is malicious and incompetent, but luckily, Android is based on linux and most of the code there is from linux.

This is of course a separate from root issue, which remains simply an issue of control: whether you want to be in control of your device or not. You can't name any OS that does not provide root to the user out of the box... Just because some (or most) smart phone dumb users don't know what they are doing does not mean that everyone should be denied root on their devices... And by the way, most Google engineers also don't know what they are doing and had it not been for Linux and the community at large, google wouldn't be able to produce anything that moves...