We need to update to latest version. Add extras-devel, extras-testing repository if you cannot find the library in the stable channel.
Enable the internet. Open terminal (Ctrl + Shift + X) and give the following commands:
1. root #change to root user (ENTER)
2 apt-get install libcurl3 (ENTER)
3.wait to be finished and restart the mobile.
Now re-validate your facebook account from the sharing accounts.