Peter Kálnai

Peter Kálnai

Senior Malware Researcher


Education: Algebra on Matfyz at Charles University in Prague

Highlights of your career: Presenting ESET on the Virus Bulletin 2016 conference

Position and history at ESET: Malware Researcher since January 2016

What malware do you hate the most? The one with hardly any invention, but very destructive impact on a victim – like crypto-ransomware.

Favorite activities: Foosball/table football. Stand-up comedians. Movies.

What is your golden rule for cyberspace? User comfort is the blue pill while security is the red one. Always choose the latter.

When did you get your first computer and what kind was it? It was in 1998. The computer was a Windows 95 PC running on an Intel Pentium processor, with 32 MB RAM and 1.7 GB hard disk.

Favorite computer game/activity: Indie games like Limbo or Machinarium now, blockbusters like NHL 98 or Settlers II then.


13 articles by Peter Kálnai

Gotta fly: Lazarus targets the UAV sector

Gotta fly: Lazarus targets the UAV sector

Gotta fly: Lazarus targets the UAV sector

ESET research analyzes a recent instance of the Operation DreamJob cyberespionage campaign conducted by Lazarus, a North Korea-aligned APT group

Peter Kálnai and Alexis Rapin • 23 Oct 2025 • 12 min. read


DeceptiveDevelopment: From primitive crypto theft to sophisticated AI-based deception

DeceptiveDevelopment: From primitive crypto theft to sophisticated AI-based deception

DeceptiveDevelopment: From primitive crypto theft to sophisticated AI-based deception

Malware operators collaborate with covert North Korean IT workers, posing a threat to both headhunters and job seekers

Peter Kálnai and Matěj Havránek • 25 Sep 2025 • 13 min. read


Lazarus luring employees with trojanized coding challenges: The case of a Spanish aerospace company

Lazarus luring employees with trojanized coding challenges: The case of a Spanish aerospace company

Lazarus luring employees with trojanized coding challenges: The case of a Spanish aerospace company

While analyzing a Lazarus attack luring employees of an aerospace company, ESET researchers discovered a publicly undocumented backdoor

Peter Kálnai • 29 Sep 2023 • 20 min. read


Linux malware strengthens links between Lazarus and the 3CX supply-chain attack

Linux malware strengthens links between Lazarus and the 3CX supply-chain attack

Linux malware strengthens links between Lazarus and the 3CX supply-chain attack

Similarities with newly discovered Linux malware used in Operation DreamJob corroborate the theory that the infamous North Korea-aligned group is behind the 3CX supply-chain attack

Peter Kálnai and Marc-Etienne M.Léveillé • 20 Apr 2023 • 12 min. read


Amazon-themed campaigns of Lazarus in the Netherlands and Belgium

Amazon-themed campaigns of Lazarus in the Netherlands and Belgium

Amazon-themed campaigns of Lazarus in the Netherlands and Belgium

ESET researchers have discovered Lazarus attacks against targets in the Netherlands and Belgium that use spearphishing emails connected to fake job offers

Peter Kálnai • 30 Sep 2022 • 18 min. read


Lazarus supply-chain attack in South Korea

Lazarus supply-chain attack in South Korea

Lazarus supply-chain attack in South Korea

ESET researchers uncover a novel Lazarus supply-chain attack leveraging WIZVERA VeraPort software

Anton Cherepanov and Peter Kálnai • 16 Nov 2020 • 15 min. read


Mikroceen: Spying backdoor leveraged in high-profile networks in Central Asia

Mikroceen: Spying backdoor leveraged in high-profile networks in Central Asia

Mikroceen: Spying backdoor leveraged in high-profile networks in Central Asia

ESET researchers dissect a backdoor deployed in attacks against multiple government agencies and major organizations operating in two critical infrastructure sectors in Asia

Peter Kálnai • 14 May 2020 • 8 min. read


Lazarus KillDisks Central American casino

Lazarus KillDisks Central American casino

Lazarus KillDisks Central American casino

The Lazarus Group gained notoriety especially after cyber-sabotage against Sony Pictures Entertainment in 2014. Fast forward to late 2017 and the group continues to deploy its malicious tools, including disk-wiping malware known as KillDisk, to attack a number of targets.

Anton Cherepanov and Peter Kálnai • 03 Apr 2018 • 7 min. read


Dangerous malware stealing bitcoin hosted on Download.com for years

Dangerous malware stealing bitcoin hosted on Download.com for years

Dangerous malware stealing bitcoin hosted on Download.com for years

ESET researchers dicovered that Trojanized applications used to steal bitcoin were hosted inadvertently by the popular website download.cnet.com.

Michal Poslušný and Peter Kálnai • 14 Mar 2018 • 5 min. read