Sorry it's not good news. Salamis Lines used to run a ferry between Haifa and Greece via Cyprus, but services have been suspended due to the political situation in the region.
I can't really think of anything useful to suggest from Sudan. If you could get to Libya via Al Awenat border crossing and then to Tunisia, you could then easily catch a ferry to France or Italy. However, I'm not able to determine whether non-Sudanese or Libyans can cross at that border. Perhaps you could check in Khartoum with the Libyan Embassy there.
Depending on when you have to be back in Europe, you could ride around via Jordan, Lebanon, Syria and Turkey. This route has been recommended by those who have taken it recently.
Or if you're short of time, you could fly the bike out of Sudan or Eritrea to Europe.
Good luck and let us know how you go!
"It matters not what goal you seek
Its secret here reposes:
You've got to dig from week to week
To get Results or Roses."
'One world, two wheels'