One Billion Android Devices Open To Privilege Escalation 117
msm1267 (2804139) writes "The first deep look into the security of the Android patch installation process, specifically its Package Management Service (PMS), has revealed a weakness that puts potentially every Android device at risk for privilege escalation attacks. Researchers from Indiana University and Microsoft published a paper that describes a new set of Android vulnerabilities they call Pileup flaws, and also introduces a new scanner called SecUP that detects malicious apps already on a device lying in wait for elevated privileges. The vulnerability occurs in the way PMS handles updates to the myriad flavors of Android in circulation today. The researchers say PMS improperly vets apps on lower versions of Android that request OS or app privileges that may not exist on the older Android version, but are granted automatically once the system is updated.
The researchers said they found a half-dozen different Pileup flaws within Android's Package Management Service, and confirmed those vulnerabilities are present in all Android Open Source Project versions and more than 3,500 customized versions of Android developed by handset makers and carriers; more than one billion Android devices are likely impacted, they said." Handily enough, the original paper is not paywalled.
The researchers said they found a half-dozen different Pileup flaws within Android's Package Management Service, and confirmed those vulnerabilities are present in all Android Open Source Project versions and more than 3,500 customized versions of Android developed by handset makers and carriers; more than one billion Android devices are likely impacted, they said." Handily enough, the original paper is not paywalled.
Re:Nope (Score:2, Insightful)
Is that even a problem? When you download an app from the Play Store, it gives you a list of permissions that the app requests. You give it permission when you download the app. If Play does not list an app if your version of Android or phone does not support the feature, then that's potentially a problem, but an easy one to fix.
HMmm (Score:2, Insightful)
Re:Nope (Score:5, Insightful)
What the summary fails to explain properly is that this vulnerability only works with permissions that are new when the device gets an OS update. Say you install an app and it asks for permission to use NFC, but your device's OS is old and doesn't support NFC (pre 4.0 I think). You install it anyway. Then you upgrade the OS and now it supports NFC. The app then gets the NFC permission without any further prompts or warning to the user.
That is certainly an issue, but not the huge gaping security flaw the summary makes it sound like. Apps can only ask for normal permissions that the OS offers, not bypass security or the sandbox. It's basically a UI issue.
Yeah, and since the carriers update Android devices so infrequently the threat exposure is more theoretical than practical.
Re:Nevertheless, I do thank MS for pointing it out (Score:4, Insightful)
"For that, I sincerely thank Microsoft for so kindly pointed out that security flaw."
"Kindly"? Are you serious? There was nothing "kind" about it. It's anti-Android PR for Microsoft. Why the hell do you think Microsoft was involved with looking into it in the first place? The goodness of their hearts? Puh-leeeeeze.
Re:Nevertheless, I do thank MS for pointing it out (Score:5, Insightful)
Considering the amount of money that Microsoft makes in patent licensing fees from Android I don't know how they could have any financial reason to want Android to go away. At the moment I suspect that Microsoft makes more money from Android than it does Windows Phone.
Re:Nevertheless, I do thank MS for pointing it out (Score:5, Insightful)
"Considering the amount of money that Microsoft makes in patent licensing fees from Android I don't know how they could have any financial reason to want Android to go away. At the moment I suspect that Microsoft makes more money from Android than it does Windows Phone."
That last bit is exactly why they want Android to go away. They don't make nearly as much money on Android as they'd make if all those same phones were Windows. Every Windows phone they can sell in place of an Android phone is more money in their pockets.
Sure, they'll make money off of Android where they can. But they'd rather it simply wasn't there.
Re:Nope (Score:5, Insightful)
The problem here is that the permissions system goes beyond just ordinary user permissions. The system itself uses permissions to control which parts of the system can do what, and those permissions are normally only available to system components (trying to install an app that asks for those permissions results in the app being rejected because it doesn't qualify to get those permissions). For instance, the "Across_users" permission was added to Android 4.2, and allows system components to break through the normal restrictions that separate different users in the system. An app with this permission can reach out and directly affect everything on the phone, not just the things that belong to it. It's restricted to Android system components only. But if I install an app that asks for it on an Android 4.0 device, the app will install without any warnings. If the device is then upgraded to 4.2, the app will silently get the "Across_users" permission activated. So now we have a user-installed app which has a permission that it could never legitimately have that lets it bypass security and the sandbox, and the user will be unaware of the problem. It's very definitely NOT just a UI issue.
In the Unix world it'd be equivalent to finding an other-writable directory sitting in the root user's PATH, and in that directory are executables named "ls", "cat" and so on. It's the kind of thing that'd make a security admin excrete cinder blocks at velocities sufficient to have them achieving high orbit, ceilings nonwithstanding.
Android has an even bigger problem with priveleges (Score:5, Insightful)
In that it still doesnt allow line-item veto of app priveleges.
This should be the most basic feature.
Re:Nope (Score:4, Insightful)
On the other hand, the likelihood of this vulnerability actually being exploited is quite low for quite a few reasons... Primarily, because it requires that you first install a malicious app and then upgrade to a version of android which actually implements some new permissions...
1, very few users ever update (or even have updates available)
2, manufacturers will sometimes patch android but usually not provide updates to whole new versions and the small incremental patches wont introduce any new permissions
3, now that this issue has been discovered its highly likely that future updates will contain a fix for it, and users are unlikely to update to a version that isnt the latest available for their particular handset, so *if* they can and do update they will be patching this issue anyway.
Android Users (Score:0, Insightful)
Android users are disgusting fat blobs who shit their pants and work at Best Buy.