Serious new claims have emerged about the Hungarian opposition TISZA Party’s possible connections to Ukrainian national security services, raising fears of foreign interference in Hungary’s 2026 elections.
The pro-Brussels party’s voter app called ‘Tisza Világ’ (‘Tisza World’) was found to have leaked thousands of people’s personal data, including names, phone numbers, email addresses, and even home addresses. The huge data leak has affected almost 20,000 users.
The full list was also posted online, which Tamás Lánczi, head of Hungary’s Sovereignty Protection Office, called “one of the most serious personal data breaches since Hungary’s democratic transition.”
According to Lánczi, there are several signs that the app was developed by a company linked to Ukrainian national security agencies. His office had already queried the TISZA Party a month ago about who created the app, where it was made, and how it was financed—but party leader Péter Magyar refused to answer.
Investigative pieces in the Hungarian media have revealed that one of the app’s administrators is Myroslav Tokar, a Ukrainian web developer who works for PettersonApps, a Ukrainian software company.
The company’s chief executive, Oleh Ostroverkh, is a supporter of President Volodymyr Zelensky and serves on the board of Defence Robotics UA, a group that builds robots and drones for the Ukrainian army’s ‘Da Vinci Wolves’ regiment.
This has caused concern in Budapest. “If people connected to Ukrainian military projects were involved in making a Hungarian political app, that raises serious security risks,” according to Ripost.
This is not the first time the TISZA Party has faced questions about its Ukrainian ties.
In 2024, Péter Magyar visited Kyiv with Roland Tseber, a politician from Ukrainian President Zelensky’s Servant of the People party. Later, Hungarian intelligence agencies identified Tseber as an illegal officer of the Ukrainian intelligence service. He was consequently expelled from Hungary last year.
Hungarian Foreign Minister Péter Szijjártó said the latest news proves that Ukraine is trying to influence next year’s Hungarian elections, “and it’s clear it is attempting to do so through the TISZA Party.” He added that Ukraine wants to help install a government in Budapest that will serve Brussels and Kyiv instead of the Hungarian people.
Relations between Hungary and Ukraine have been tense for years.
Hungary has refused to send weapons to Ukraine and has criticised Kyiv for mistreating the Hungarian minority in Transcarpathia. Meanwhile, President Zelensky has attacked Orbán for blocking Ukraine’s bid to join the European Union. Orbán responded that “no country has ever blackmailed its way into the EU—and it won’t happen this time either.”
The discovery that a Ukrainian tech company may have had access to the personal data of thousands of Hungarians has only exacerbated the already strained relationship. The Sovereignty Protection Office warned that the leak could be used for foreign influence operations, disinformation, or election meddling.
Despite the scandal, the TISZA app is still active, and the party has not stopped collecting user data.
