Krebs on Security

In-depth security news and investigation

  1. Netherlands Seizes 800 Servers, Arrests 2 for Aiding Cyberattacks

    Authorities in the Netherlands have arrested the co-owners of two related Internet hosting companies for operating IT infrastructure used by Russia to carry out cyberattacks, influence operations and disinformation campaigns inside the European Union. The two men were the focus of a 2025 KrebsOnSecurity story about how their hosting companies had assumed control over the technical infrastructure of Stark Industries Solutions, an Internet service provider sanctioned last year by the EU as a frequent staging ground for cyber mischief from Russia's intelligence agencies.

  2. Lawmakers Demand Answers as CISA Tries to Contain Data Leak

    Lawmakers in both houses of Congress are demanding answers from the U.S. Cybersecurity & Infrastructure Security Agency (CISA) after KrebsOnSecurity reported this week that a CISA contractor intentionally published AWS GovCloud keys and a vast trove of other agency secrets on a public GitHub account. The inquiry comes as CISA is still struggling to contain the breach and invalidate the leaked credentials.

  3. Alleged Kimwolf Botmaster ‘Dort’ Arrested, Charged in U.S. and Canada

    Canadian authorities on Wednesday arrested a 23-year-old Ottawa man on suspicion of building and operating Kimwolf, a fast spreading Internet-of-Things botnet that enslaved millions of devices for use in a series of massive distributed denial-of-service (DDoS) attacks over the past six months. KrebsOnSecurity publicly named the suspect in February 2026 after the accused launched a volley of DDoS, doxing and swatting campaigns against this author and a security researcher. He now faces criminal hacking charges in both Canada and the United States.

  4. CISA Admin Leaked AWS GovCloud Keys on Github

    Until this past weekend, a contractor for the Cybersecurity & Infrastructure Security Agency (CISA) maintained a public GitHub repository that exposed credentials to several highly privileged AWS GovCloud accounts and a large number of internal CISA systems. Security experts said the public archive included files detailing how CISA builds, tests and deploys software internally, and that it represents one of the most egregious government data leaks in recent history.

  5. Patch Tuesday, May 2026 Edition

    Artificial intelligence platforms may be just as susceptible to social engineering as human beings, but they are proving remarkably good at finding security vulnerabilities in human-made computer code. That reality is on full display this month with some of the more widely-used software makers -- including Apple, Google, Microsoft, Mozilla and Oracle -- fixing near record volumes of security bugs, and/or quickening the tempo of their patch releases.

  6. Canvas Breach Disrupts Schools & Colleges Nationwide

    An ongoing data extortion attack targeting the widely-used education technology platform Canvas disrupted classes and coursework at school districts and universities across the United States today, after a cybercrime group defaced the service's login page with a ransom demand that threatened to leak data from 275 million students and faculty across nearly 9,000 educational institutions.

  7. Anti-DDoS Firm Heaped Attacks on Brazilian ISPs

    A Brazilian tech firm that specializes in protecting networks from distributed denial-of-service (DDoS) attacks has been enabling a botnet responsible for an extended campaign of massive DDoS attacks against other network operators in Brazil, KrebsOnSecurity has learned. The firm's chief executive says the malicious activity resulted from a security breach and was likely the work of a competitor trying to tarnish his company's public image.

  8. ‘Scattered Spider’ Member ‘Tylerb’ Pleads Guilty

    A 24-year-old British national and senior member of the cybercrime group "Scattered Spider" has pleaded guilty to wire fraud conspiracy and aggravated identity theft. Tyler Robert Buchanan admitted his role in a series of text-message phishing attacks in the summer of 2022 that allowed the group to hack into at least a dozen major technology companies and steal tens of millions of dollars worth of cryptocurrency from investors.

  9. Patch Tuesday, April 2026 Edition

    Microsoft today pushed software updates to fix a staggering 167 security vulnerabilities in its Windows operating systems and related software, including a SharePoint Server zero-day and a publicly disclosed weakness in Windows Defender dubbed "BlueHammer." Separately, Google Chrome fixed its fourth zero-day of 2026, and an emergency update for Adobe Reader nixes an actively exploited flaw that can lead to remote code execution.

  10. Russia Hacked Routers to Steal Microsoft Office Tokens

    Hackers linked to Russia's military intelligence units are using known flaws in older Internet routers to mass harvest authentication tokens from Microsoft Office users, security experts warned today. The spying campaign allowed state-backed Russian hackers to quietly siphon authentication tokens from users on more than 18,000 networks without deploying any malicious software or code.