Corrupt employer, reporting mechanisms?

Very sorry to hear that!
First of all, do know that such things even happen to locals, quite frequently.
Most offenses go unreported, because most employment contracts include something fraudulent or incriminating for the employee as well: part of the wage paid under the table, health insurance benefits fraud, etc.
At other times, bonuses and wages are delayed and the employee keeps quiet in fear of losing the money he is owed.
And with the unemployment rate so high, most people feel lucky to have a job even while abused, they fear it might take prohibitively long to find another one (especially if they have a bad reputation among employers)

So if in your situation you know you did nothing wrong, everything was legal from your side, you already incurred the financial losses and you are sure you are not risking losing your residency or whatever status by getting in a labor dispute, you decide to go through with it and get a favorable judgment, that's still not money in the bank: Depending on the size of your employer and the amount owed/awarded, there is still a possibility for your employer to fake bankruptcy, pay you nothing and continue the next day where he left off with the serial number in the company name incremented by one.

You don't give too many details, so I can't be sure, but it looks like you don't have much to lose by contacting the authorities:

Labor Office (they do inspections on work safety and labor law compliance)
http://www.ommf.gov.hu/index.html?akt_menu=206

Tax authority (all-powerful, above the law in many ways. I'm sure you witnessed tax evasion)
http://nav.gov.hu/nav/bunugy/elerhetose … toseg.html

Very popular site to publicly name and shame offenders, often featured on the largest news site index.hu:
http://munkahelyiterror.blog.hu/


Let us know how we can help, PM me if it's too sensitive to just post publicly.