suspicious shared libs in /system/lib - Android Q&A, Help & Troubleshooting

device is:
ST70208-1
Android Version: 4.1.1
Kernel Version: 3.0.8+
Build: ST70208-1_20130808_INT
aka Trekstor Surftab Ventos 7.0 HD
As Chrome crashes at start even after factory reset and all known measures did not help,
i installed root/su/bussybox/ssh-server and did a logcat.
...
/ActivityManager( 3603): Start proc com.android.chrome:sandboxed_process0 for service com.android.chrome/org.chromium.content.app.SandboxedProcessService0: pid=24769 uid=99001 gids={}
I/LibraryLoader(24750): loading: chromeview
E/Main (24750): Failed to load native library.
E/Main (24750): org.chromium.content.common.ProcessInitException
E/Main (24750): at org.chromium.content.app.LibraryLoader.loadNow(Unknown Source)
E/Main (24750): at com.google.android.apps.chrome.Main$InitializerContinuation.loadLibraryNow(Unknown Source)
E/Main (24750): at com.google.android.apps.chrome.Main$InitializerContinuation.access$400(Unknown Source)
E/Main (24750): at com.google.android.apps.chrome.Main$InitializerContinuation$2.run(Unknown Source)
E/Main (24750): at android.os.Handler.handleCallback(Handler.java:615)
E/Main (24750): at android.os.Handler.dispatchMessage(Handler.java:92)
E/Main (24750): at android.os.Looper.loop(Looper.java:137)
E/Main (24750): at android.os.HandlerThread.run(HandlerThread.java:60)
E/Main (24750): Caused by: java.lang.UnsatisfiedLinkError: Cannot load library: link_image[1891]: 2487 could not load needed library 'libjnigraphics.so' for 'libchromeview.so' (load_library[1093]: Library 'libjnigraphics.so' not found)
E/Main (24750): at java.lang.Runtime.loadLibrary(Runtime.java:370)
E/Main (24750): at java.lang.System.loadLibrary(System.java:535)
E/Main (24750): ... 8 more
E/Trace (24769): error opening trace file: No such file or directory (2)
D/OpenGLRenderer(24750): Enabling debug mode 0
I/SandboxedProcessService(24769): Creating new SandboxedProcessService pid=24769
I/LibraryLoader(24769): loading: chromeview
E/SandboxedProcessService(24769): Failed to load native library, exiting sandboxed process
E/SandboxedProcessService(24769): org.chromium.content.common.ProcessInitException
E/SandboxedProcessService(24769): at org.chromium.content.app.LibraryLoader.loadNow(Unknown Source)
E/SandboxedProcessService(24769): at org.chromium.content.app.SandboxedProcessService$2.run(Unknown Source)
E/SandboxedProcessService(24769): at java.lang.Thread.run(Thread.java:856)
E/SandboxedProcessService(24769): Caused by: java.lang.UnsatisfiedLinkError: Cannot load library: link_image[1891]: 2487 could not load needed library 'libjnigraphics.so' for 'libchromeview.so' (load_library[1093]: Library 'libjnigraphics.so' not found)
E/SandboxedProcessService(24769): at java.lang.Runtime.loadLibrary(Runtime.java:370)
E/SandboxedProcessService(24769): at java.lang.System.loadLibrary(System.java:535)
E/SandboxedProcessService(24769): ... 3 more
..
"ls -al" in /system/lib showed amongst others 4 suspicious shared native libraries:
-rw------- 1 0 0 59996 Mar 17 18:50 libjnigraphics.so
-rw------- 1 0 0 10017928 Mar 17 18:18 libmsrmsdk.so
-rw------- 1 0 0 8577120 Mar 17 18:50 libreader.so
-rw------- 1 0 0 135864 Mar 17 18:51 librss.so
all other libs here look like that:
-rw-r--r-- 1 0 0 31363328 Aug 1 2008 libchromeview.so
The 4 suspects have a date 03/17/2016 and no read permission for group/other but the rest all are 8/1/2008 and have the permissions.
I did "chmod 644" to them.
But i had to remount /system as readwrite.
Seams it is normaly readonly!
And i had to do "su"!
How/Who can change anything here in /system/lib?
Chrom still crashes but logcat shows it is not because it does not find the libjnigraphics.so.
Now it crashes with a dump.
I think it is because libchromeview.so loads the dependency libjnigraphics.so,
but that is an newer version than that it was linked against.
After i left the device in the morning on the day this **** happend, it was working ok.
In the evening (my wife had used it) there was tones of error msg at starting of many apps (Contacts, Playstore, ...).
So i did a factory reset, but the Chrome problem persists (Google+ and Maps where *****y too but worked after update).
I did not switch of auto update.
So i think some update messed it up, or my wife had switched it hard off during something important/longer lasting, as it was not responsive to her.
But how can a normal apk do something to /system?!
Any ideas why Chrome still uses these old native shared libraries?
Please can somebody who is having the same device, send me a "ls -al" of /system/lib.
Any ideas how to fix Chrome (PlayStore)?
Greetings
Michael
PS: This was the 3rd factory reset i had to make because some update managed to screwed it. But the two before worked, ok.
The stock "firmware" of this device looks as if it was the 5th test build a new greenhorn system builder.
And ADB does not work. The device announces itself only in recovery mode to USB (of course "USB debugging" is on).