Use usb debugging to 'backup' the malware
adb pull /system/app/
Download original firmware
wget http://img.irulu.com/driver/U2_Q500H_V101En20141223.rar
unrar e U2_Q500H_V101En20141223.rar
$ file system.img
system.img: Android sparse image, version: 1.0, Total of 256000 4096-byte output blocks in 1684 input chunks.
Now to check if the original firmware is clean
git clone https://github.com/anestisb/android-simg2img.git
make
Mount the system image
$ file system.raw.img
system.raw.img: Linux rev 1.0 ext4 filesystem data, UUID=57f8f4bc-abf4-655f-bf67-946fc0f9f25b (needs journal recovery) (extents) (large files)
sudo mount -o loop system.raw.img /mnt/loop/
Compare with that found on the Ali Express phone reveals
diff sys_app_mal.ls sys_app_irulu.ls
1d0
< abc.apk
24d22
< cd89920009
29d26
< com.andr0id.lauchinmg.apk
31,43d27
< com.as.youtube.downloader.a5.apk
< com.chaidongqiang.beautyvideo.apk
< com.example.homeof01111beauty.apk
< com.example.homeof01192beauty.apk
< com.free.all.mp3.music.a6.apk
< com.free.all.mptree.music.b.apk
< com.haodu.sexyhotvideo.apk
< com.json.lutu.apk
< com.sailer.coolbrowser.apk
< com.sms.server.socialgraphop.db
< com.swiping.whale.apk
< com.system.cap.hm.hupdater.apk
< com.system.update.apk
45,46d28
< CustomICON.apk
< CustomICON.odex
75c57
< frozenkeyboard.apk
---
> Frozen_Keyboard.apk
82d63
< GloablBCServiceInfo.apk
89d69
< hll_videoplayer_pop.apk
92a73
> HTMLViewer.odex
125d105
< obs.apk
130d109
< OPBKEY_4c16012fb8540b4619b866cb3dde30aecf5f
141c120
< playApp.apk
---
> playApp_0830.apk
165d143
< system.bin.apk
178d155
< v5_function_video.mp4
180a158
> videoplayer.apk
So, the original firmware looks OK - now, to install it
I was unable to unlock the fastboot, so I used this procedure instead -
Download SP Flash Tool for Linux from -
(or elsewhere. Note that the Windows version I grabbed, included Malware)
Uninstall ModemManager
sudo yum remove ModemManager
sudo udevadm control --reload
Power off the phone
Start the tool
sudo SP_Flash_Tool_v5.1548_Linux/flash_tool.sh
On the Download tab, select the scatter file from the extracted Irulu file (MT6582_Android_scatter.txt)
Click download
Now, power on the phone
Download should progress and show OK
Disconnect and power cycle the phone, and all should be good!