I wrote in my C.V that I am specialized in engineering although it is not true; consequently, I was recruited since 4 years in a foreign company specialized in petroleum field. What is the ruling on this?
All perfect praise be to Allah, The Lord of The Worlds, and may His peace and blessings be upon our Prophet Muhammad and upon all of his family and companions.
Allah, The Exalted prohibited lie, cheating and fraud for He said (What means):” O ye who believe! Be careful of your duty to Allah, and be with the truthful.” [At-Tawbah/119], in addition the Prophet (PBUH) said (What means):” Should I inform you out the greatest of the great sins?" They said, "Yes, O Allah's Messenger (ﷺ)!" He said, "To join others in worship with Allah and to be undutiful to one's parents." The Prophet (ﷺ) then sat up after he had been reclining (on a pillow) and said, "And I warn you against giving a false witness, and he kept on saying that warning till we thought he would not stop.” [Related by Al-Bukhary].
Therefore, you (Questioner) are not permitted to proceed in the job in order to free yourself from the liability before Allah since you earned it through fake certificate although certain qualifications and abilities are required in this critical field.
Finally, you are obliged for offering sincere repentance as it entails you to avoid committing similar acts once again and to give charity as much as you could. And Allah knows best.