A 21-year-old man from Vancouver, Wash. has pleaded guilty to federal hacking charges tied to his role in operating the "Satori" botnet, a crime machine powered by hacked Internet of Things (IoT) devices that was built to conduct massive denial-of-service attacks targeting Internet service providers, online gaming platforms and Web hosting companies.

Many spam trends are cyclical: Spammers tend to switch tactics when one method of hijacking your time and attention stops working. But periodically they circle back to old tricks, and few spam trends are as perennial as calendar spam, in which invitations to click on dodgy links show up unbidden in your digital calendar application from Apple, Google and Microsoft. Here's a brief primer on what you can do about it.

Federal prosecutors in California have filed criminal charges against four employees of Adconion Direct, an email advertising firm, alleging they unlawfully hijacked vast swaths of Internet addresses and used them in large-scale spam campaigns. KrebsOnSecurity has learned that the charges are likely just the opening salvo in a much larger, ongoing federal investigation into the company's commercial email practices.

Many companies are now outsourcing their marketing efforts to cloud-based Customer Relationship Management (CRM) providers. But when accounts at those CRM providers get hacked or phished, the results can be damaging for both the client's brand and their customers. Here's a look at a recent CRM-based phishing campaign that targeted customers of Fortune 500 construction equipment vendor United Rentals.

PerCSoft, a Wisconsin-based company that manages a remote data backup service relied upon by hundreds of dental offices across the country, is struggling to restore access to client systems after falling victim to a ransomware attack.

Imperva, a leading provider of Internet firewall services that help Web sites block malicious cyberattacks, alerted customers on Tuesday that a recent data breach exposed email addresses, scrambled passwords, API keys and SSL certificates for a subset of its firewall users. Redwood Shores, Calif.-based Imperva sells firewall technology designed to detect and block various types of malicious Web traffic, from denial-of-service attacks to digital probes aimed at undermining the security of Web-based software applications.

On Tuesday of this week, one of the more popular underground stores peddling credit and debit card data stolen from hacked merchants announced a blockbuster new sale: More than 5.3 million new accounts belonging to cardholders from 35 U.S. states. Multiple sources now tell KrebsOnSecurity that the card data came from compromised gas pumps, coffee shops and restaurants operated by Hy-Vee, an Iowa-based company that operates a chain of more than 245 supermarkets throughout the Midwestern United States.

Almost weekly now I hear from an indignant reader who suspects a data breach at a Web site they frequent that has just asked the reader to reset their password. Further investigation almost invariably reveals that the password reset demand was not the result of a breach but rather the site's efforts to identify customers who are reusing passwords from other sites that have already been hacked. But ironically, many companies taking these proactive steps soon discover that their explanation as to why they're doing it can get misinterpreted as more evidence of lax security. This post attempts to unravel what's going on here.