‘Popa’ Botnet Linked to Publicly-Traded Israeli Firm

For the past four years, a sprawling Android-based botnet called Popa has forced millions of consumer TV boxes to relay Internet traffic linked to advertising fraud, account takeovers, and mass data-scraping efforts. This week, researchers from multiple security firms concluded that the Popa botn...

Who Runs the Ransomware Group ‘The Gentlemen?’

A cybercrime group known as The Gentlemen has emerged as the second most active ransomware gang by victim count, rapidly attracting a talented pool of hackers through an aggressive recruitment strategy that promises affiliates 90 percent of any ransom paid by victims. This post examines clues...

A Record-Breaking Patch Tuesday for June 2026

Microsoft today released software updates to plug nearly 200 security holes across its Windows operating systems and supported software, a record number of fixes for the company's monthly Patch Tuesday cycle. Nearly three dozen of those bugs earned Microsoft's most dire "critical" rating, and...

Hackers Used Meta’s AI Support Bot to Seize Instagram Accounts

The Instagram accounts for the Obama White House and the Chief Master Sergeant of the U.S. Space Force were briefly defaced with pro-Iranian images and messages over the weekend, after instructions began circulating on Telegram showing how to trick Meta's "AI support assistant" bot into resetting...

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...

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 accoun...

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...

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...

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 --...

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...

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...

‘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...

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...

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...

Germany Doxes “UNKN,” Head of RU Ransomware Gangs REvil, GandCrab

An elusive hacker who went by the handle "UNKN " and ran the early Russian ransomware groups GandCrab and REvil now has a name and a face. Authorities in Germany say 31-year-old Russian Daniil Maksimovich Shchukin headed both cybercrime gangs and helped carry out at least 130 acts of computer...

‘CanisterWorm’ Springs Wiper Attack Targeting Iran

A financially motivated data theft and extortion group is attempting to inject itself into the Iran war, unleashing a worm that spreads through poorly secured cloud services and wipes data on infected systems that use Iran's time zone or have Farsi set as the default language. Experts say the wip...

Feds Disrupt IoT Botnets Behind Huge DDoS Attacks

The U.S. Justice Department joined authorities in Canada and Germany in dismantling the online infrastructure behind four highly disruptive botnets that compromised more than three million Internet of Things IoT devices, such as routers and web cameras. The feds say the four botnets -- named Aisu...

Iran-Backed Hackers Claim Wiper Attack on Medtech Firm Stryker

A hacktivist group with links to Iran's intelligence agencies is claiming responsibility for a data-wiping attack against Stryker , a global medical technology company based in Michigan. News reports out of Ireland, Stryker's largest hub outside of the United States, said the company sent home mo...

Microsoft Patch Tuesday, March 2026 Edition

Microsoft Corp. today pushed security updates to fix at least 77 vulnerabilities in its Windows operating systems and other software. There are no pressing "zero-day" flaws this month compared to February's five zero-day treat, but as usual some patches may deserve more rapid attention from...

How AI Assistants are Moving the Security Goalposts

AI-based assistants or "agents" -- autonomous programs that have access to the user's computer, files, online services and can automate virtually any task -- are growing in popularity with developers and IT workers. But as so many eyebrow-raising headlines over the past few weeks have shown, thes...

Who is the Kimwolf Botmaster “Dort”?

In early January 2026, KrebsOnSecurity revealed how a security researcher disclosed a vulnerability that was used to build Kimwolf , the world's largest and most disruptive botnet. Since then, the person in control of Kimwolf -- who goes by the handle "Dort " -- has coordinated a barrage of...

‘Starkiller’ Phishing Service Proxies Real Login Pages, MFA

Most phishing websites are little more than static copies of login pages for popular online destinations, and they are often quickly taken down by anti-abuse activists and security firms. But a stealthy new phishing-as-a-service offering lets customers sidestep both of these pitfalls: It uses...

Kimwolf Botnet Swamps Anonymity Network I2P

For the past week, the massive "Internet of Things" IoT botnet known as Kimwolf has been disrupting The Invisible Internet Project I2P, a decentralized, encrypted communications network designed to anonymize and secure online communications. I2P users started reporting disruptions in the network...

Patch Tuesday, February 2026 Edition

Microsoft today released updates to fix more than 50 security holes in its Windows operating systems and other software, including patches for a whopping six "zero-day" vulnerabilities that attackers are already exploiting in the wild. Zero-day 1 this month is CVE-2026-21510, a security feature...

Please Don’t Feed the Scattered Lapsus ShinyHunters

A prolific data ransom gang that calls itself Scattered Lapsus ShinyHunters SLSH has a distinctive playbook when it seeks to extort payment from victim firms: Harassing, threatening and even swatting executives and their families, all while notifying journalists and regulators about the extent of...

Who Operates the Badbox 2.0 Botnet?

The cybercriminals in control of Kimwolf -- a disruptive botnet that has infected more than 2 million devices -- recently shared a screenshot indicating they'd compromised the control panel for Badbox 2.0 , a vast China-based botnet powered by malicious software that comes pre-installed on many...

Kimwolf Botnet Lurking in Corporate, Govt. Networks

A new Internet-of-Things IoT botnet called Kimwolf has spread to more than 2 million devices, forcing infected systems to participate in massive distributed denial-of-service DDoS attacks and to relay other malicious and abusive Internet traffic. Kimwolf's ability to scan the local networks of...

Patch Tuesday, January 2026 Edition

Microsoft today issued patches to plug at least 113 security holes in its various Windows operating systems and supported software. Eight of the vulnerabilities earned Microsoft's most-dire "critical" rating, and the company warns that attackers are already exploiting one of the bugs fixed today...

Who Benefited from the Aisuru and Kimwolf Botnets?

Our first story of 2026 revealed how a destructive new botnet called Kimwolf has infected more than two million devices by mass-compromising a vast number of unofficial Android TV streaming boxes. Today, we'll dig through digital clues left behind by the hackers, network operators and services th...

The Kimwolf Botnet is Stalking Your Local Network

The story you are reading is a series of scoops nestled inside a far more urgent Internet-wide security advisory. The vulnerability at issue has been exploited for months already, and it's time for a broader awareness of the threat. The short version is that everything you thought you knew about...

Happy 16th Birthday, KrebsOnSecurity.com!

KrebsOnSecurity.com celebrates its 16th anniversary today! A huge "thank you" to all of our readers -- newcomers, long-timers and drive-by critics alike. Your engagement this past year here has been tremendous and truly a salve on a handful of dark days. Happily, comeuppance was a strong theme...

Dismantling Defenses: Trump 2.0 Cyber Year in Review

The Trump administration has pursued a staggering range of policy pivots this past year that threaten to weaken the nation's ability and willingness to address a broad spectrum of technology challenges, from cybersecurity and privacy to countering disinformation, fraud and corruption. These shift...

Most Parked Domains Now Serving Malicious Content

Direct navigation -- the act of visiting a website by manually typing a domain name in a web browser -- has never been riskier: A new study finds the vast majority of "parked" domains -- mostly expired or dormant domain names, or common misspellings of popular websites -- are now configured to...

Microsoft Patch Tuesday, December 2025 Edition

Microsoft today pushed updates to fix at least 56 security flaws in its Windows operating systems and supported software. This final Patch Tuesday of 2025 tackles one zero-day bug that is already being exploited, as well as two publicly disclosed vulnerabilities. Despite releasing a...

Drones to Diplomas: How Russia’s Largest Private University is Linked to a $25M Essay Mill

A sprawling academic cheating network turbocharged by Google Ads that has generated nearly $25 million in revenue has curious ties to a Kremlin-connected oligarch whose Russian university builds drones for Russia's war against Ukraine. The Nerdify homepage. The link between essay mills and Russia...

SMS Phishers Pivot to Points, Taxes, Fake Retailers

China-based phishing groups blamed for non-stop scam SMS messages about a supposed wayward package or unpaid toll fee are promoting a new offering, just in time for the holiday shopping season: Phishing kits for mass-creating fake but convincing e-commerce websites that convert customer payment...

Meet Rey, the Admin of ‘Scattered Lapsus$ Hunters’

A prolific cybercriminal group that calls itself "Scattered LAPSUS$ Hunters " has dominated headlines this year by regularly stealing data from and publicly mass extorting dozens of major corporations. But the tables seem to have turned somewhat for "Rey," the moniker chosen by the technical...

Is Your Android TV Streaming Box Part of a Botnet?

On the surface, the Superbox media streaming devices for sale at retailers like BestBuy and Walmart may seem like a steal: They offer unlimited access to more than 2,200 pay-per-view and streaming services like Netflix , ESPN and Hulu , all for a one-time fee of around $400. But security experts...

Mozilla Says It’s Finally Done With Two-Faced Onerep

In March 2024, Mozilla said it was winding down its collaboration with Onerep -- an identity protection service offered with the Firefox web browser that promises to remove users from hundreds of people-search sites -- after KrebsOnSecurity revealed Onerep's founder had created dozens of...

The Cloudflare Outage May Be a Security Roadmap

An intermittent outage at Cloudflare on Tuesday briefly knocked many of the Internet's top destinations offline. Some affected Cloudflare customers were able to pivot away from the platform temporarily so that visitors could still access their websites. But security experts say doing so may have...

Microsoft Patch Tuesday, November 2025 Edition

Microsoft this week pushed security updates to fix more than 60 vulnerabilities in its Windows operating systems and supported software, including at least one zero-day bug that is already being exploited. Microsoft also fixed a glitch that prevented some Windows 10 users from taking advantage of...

Google Sues to Disrupt Chinese SMS Phishing Triad

Google is suing more than two dozen unnamed individuals allegedly involved in peddling a popular China-based mobile phishing service that helps scammers impersonate hundreds of trusted brands, blast out text message lures, and convert phished payment card data into mobile wallets from Apple and...

Drilling Down on Uncle Sam’s Proposed TP-Link Ban

The U.S. government is reportedly preparing to ban the sale of wireless routers and other networking gear from TP-Link Systems , a tech company that currently enjoys an estimated 50% market share among home users and small businesses. Experts say while the proposed ban may have more to do with...

Cloudflare Scrubs Aisuru Botnet from Top Domains List

For the past week, domains associated with the massive Aisuru botnet have repeatedly usurped Amazon , Apple , Google and Microsoft in Cloudflare's public ranking of the most frequently requested websites. Cloudflare responded by redacting Aisuru domain names from their top websites list. The chie...

Alleged Jabber Zeus Coder ‘MrICQ’ in U.S. Custody

A Ukrainian man indicted in 2012 for conspiring with a prolific hacking group to steal tens of millions of dollars from U.S. businesses was arrested in Italy and is now in custody in the United States, KrebsOnSecurity has learned. Sources close to the investigation say Yuriy Igorevich Rybtsov , a...

Aisuru Botnet Shifts from DDoS to Residential Proxies

Aisuru , the botnet responsible for a series of record-smashing distributed denial-of-service DDoS attacks this year, recently was overhauled to support a more low-key, lucrative and sustainable business: Renting hundreds of thousands of infected Internet of Things IoT devices to proxy services...

Canada Fines Cybercrime Friendly Cryptomus $176M

Financial regulators in Canada this week levied $176 million in fines against Cryptomus , a digital payments platform that supports dozens of Russian cryptocurrency exchanges and websites hawking cybercrime services. The penalties for violating Canada's anti money-laundering laws come ten months...

Email Bombs Exploit Lax Authentication in Zendesk

Cybercriminals are abusing a widespread lack of authentication in the customer service platform Zendesk to flood targeted email inboxes with menacing messages that come from hundreds of Zendesk corporate customers simultaneously. Zendesk is an automated help desk service designed to make it simpl...

Patch Tuesday, October 2025 ‘End of 10’ Edition

Microsoft today released software updates to plug a whopping 172 security holes in its Windows operating systems, including at least two vulnerabilities that are already being actively exploited. October's Patch Tuesday also marks the final month that Microsoft will ship security updates for...

DDoS Botnet Aisuru Blankets US ISPs in Record DDoS

The world's largest and most disruptive botnet is now drawing a majority of its firepower from compromised Internet-of-Things IoT devices hosted on U.S. Internet providers like AT &T, Comcast and Verizon , new evidence suggests. Experts say the heavy concentration of infected devices at U.S...