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 simple for people to contact companies for …

A cybercriminal group that used voice phishing attacks to siphon more than a billion records from Salesforce customers earlier this year has launched a website that threatens to publish data stolen from dozens of Fortune 500 firms if they refuse to pay a ransom. The group also claimed responsibility …

U.S. prosecutors last week levied criminal hacking charges against 19-year-old U.K. national Thalha Jubair for allegedly being a core member of Scattered Spider, a prolific cybercrime group blamed for extorting at least $115 million in ransom payments from victims. The charges came as Jubair and an alleged …

In May 2025, the European Union levied financial sanctions on the owners of Stark Industries Solutions Ltd., a bulletproof hosting provider that materialized two weeks before Russia invaded Ukraine and quickly became a top source of Kremlin-linked cyberattacks and disinformation campaigns. But new findings show those sanctions have done …

At least 18 popular JavaScript code packages that are collectively downloaded more than two billion times each week were briefly compromised with malicious software today, after a developer involved in maintaining the projects was phished. The attack appears to have been quickly contained and was narrowly focused on stealing …

The chairman of the Federal Trade Commission (FTC) last week sent a letter to Google’s CEO demanding to know why Gmail was blocking messages from Republican senders while allegedly failing to block similar missives supporting Democrats. The letter followed media reports accusing Gmail of disproportionately flagging messages from …

The recent mass-theft of authentication tokens from Salesloft, whose AI chatbot is used by a broad swath of corporate America to convert customer interaction into Salesforce leads, has left many companies racing to invalidate the stolen credentials before hackers can exploit them. Now Google warns the breach goes far …

Last month, KrebsOnSecurity tracked the sudden emergence of hundreds of polished online gaming and wagering websites that lure people with free credits and eventually abscond with any cryptocurrency funds deposited by players. We’ve since learned that these scam gambling sites have proliferated thanks to a new Russian affiliate …

The cybersecurity community on Reddit responded in disbelief this month when a self-described Air National Guard member with top secret security clearance began questioning the arrangement they’d made with company called DSLRoot, which was paying $250 a month to plug a pair of laptops into the Redditor’s …

A 22-year-old Oregon man has been arrested on suspicion of operating “ Rapper Bot,” a massive botnet used to power a service for launching distributed denial-of-service (DDoS) attacks against targets — including a March 2025 DDoS that knocked Twitter/X offline. The Justice Department asserts the suspect and an unidentified co-conspirator …

Cybercriminal groups peddling sophisticated phishing kits that convert stolen card data into mobile wallets have recently shifted their focus to targeting customers of brokerage services, new research shows. Undeterred by security controls at these trading platforms that block users from wiring funds directly out of accounts, the phishers have …

A new documentary series about cybercrime airing next month on HBO Max features interviews with Yours Truly. The four-part series follows the exploits of Julius Kivimäki, a prolific Finnish hacker recently convicted of leaking tens of thousands of patient records from an online psychotherapy practice while attempting to extort …

Fraudsters are flooding Discord and other social media platforms with ads for hundreds of polished online gaming and wagering websites that lure people with free credits and eventually abscond with any cryptocurrency funds deposited by players. Here’s a closer look at the social engineering tactics and remarkable traits …

KrebsOnSecurity recently heard from a reader whose boss’s email account got phished and was used to trick one of the company’s customers into sending a large payment to scammers. An investigation into the attacker’s infrastructure points to a long-running Nigerian cybercrime ring that is actively targeting …

Security researchers recently revealed that the personal information of millions of people who applied for jobs at McDonald’s was exposed after they guessed the password (“123456”) for the fast food chain’s account at Paradox.ai, a company that makes artificial intelligence based hiring chatbots used by many …

Marko Elez, a 25-year-old employee at Elon Musk’s Department of Government Efficiency (DOGE), has been granted access to sensitive databases at the U.S. Social Security Administration, the Treasury and Justice departments, and the Department of Homeland Security. So it should fill all Americans with a deep sense …

In May 2025, the U.S. government sanctioned a Chinese national for operating a cloud provider linked to the majority of virtual currency investment scam websites reported to the FBI. But a new report finds the accused continues to operate a slew of established accounts at American tech companies …

Agents with the Federal Bureau of Investigation (FBI) briefed Capitol Hill staff recently on hardening the security of their mobile devices, after a contacts list stolen from the personal phone of the White House Chief of Staff Susie Wiles was reportedly used to fuel a series of text messages …

Late last year, security researchers made a startling discovery: Kremlin-backed disinformation campaigns were bypassing moderation on social media platforms by leveraging the same malicious advertising technology that powers a sprawling ecosystem of online hucksters and website hackers. A new report on the fallout from that investigation finds this dark …

Image: Mark Rademaker, via Shutterstock. Ukraine has seen nearly one-fifth of its Internet space come under Russian control or sold to Internet address brokers since February 2022, a new study finds. The analysis indicates large chunks of Ukrainian Internet address space are now in the hands of shadowy proxy …

Image: Shutterstock, ArtHead. The U.S. government today imposed economic sanctions on Funnull Technology Inc., a Philippines-based company that provides computer infrastructure for hundreds of thousands of websites involved in virtual currency investment scams known as “ pig butchering.” In January 2025, KrebsOnSecurity detailed how Funnull was being used as …

Authorities in Pakistan have arrested 21 individuals accused of operating “ Heartsender,” a once popular spam and malware dissemination service that operated for more than a decade. The main clientele for HeartSender were organized crime groups that tried to trick victim companies into making payments to a third party, and …

The U.S. government today unsealed criminal charges against 16 individuals accused of operating and selling DanaBot, a prolific strain of information-stealing malware that has been sold on Russian cybercrime forums since 2018. The FBI says a newer version of DanaBot was used for espionage, and that many of …

KrebsOnSecurity last week was hit by a near record distributed denial-of-service (DDoS) attack that clocked in at more than 6.3 terabits of data per second (a terabit is one trillion bits of data). The brief attack appears to have been a test run for a massive new Internet …

In what experts are calling a novel legal outcome, the 22-year-old former administrator of the cybercrime community Breachforums will forfeit nearly $700,000 to settle a civil lawsuit from a health insurance company whose customer data was posted for sale on the forum in 2023. Conor Brian Fitzpatrick, a …