The Malware tag covers malware families, infrastructure analysis, incident impact, disruption efforts, and defensive guidance to reduce cybersecurity risk.
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Background for this topic.
Malware is software intentionally created or modified to perform unauthorized or harmful actions on a computer, device, or network. The term covers distinct families and functions, including viruses, worms, trojans, spyware, botnet clients, and ransomware; a single sample may combine several capabilities. Its behavior—not its label—determines the security concern: it may execute code, persist, alter or encrypt data, steal credentials, or provide unauthorized remote access.
For practitioners, malware reporting is most useful when it identifies the family or tool conservatively and provides evidence such as affected platforms, samples, infrastructure, or observed behavior. Defenses include promptly patching vulnerable software, restricting execution and privileges, monitoring endpoints and networks, maintaining tested backups, and isolating suspected systems for analysis. Detection should use behavior and verified indicators rather than names alone, since variants change. If malware processes personal or regulated data, investigations should also address privacy, evidence preservation, and applicable reporting obligations.
Weekly headline count for the current query.
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 redirect visitors to sites that foist scams and malware.
At least 187 code packages made available through the JavaScript repository NPM have been infected with a self-replicating worm that steals credentials from developers and publishes those secrets on GitHub, experts warn. The malware, which briefly infected multiple code packages from the security vendor CrowdStrike, steals and publishes even more credentials every time an infected package is installed.
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 cryptocurrency. But experts warn that a similar attack with a slightly more nefarious payload could quickly lead to a disruptive malware outbreak that is far more difficult to detect and restrain.
Microsoft today released updates to fix more than 100 security flaws in its Windows operating systems and other software. At least 13 of the bugs received Microsoft's most-dire "critical" rating, meaning they could be abused by malware or malcontents to gain remote access to a Windows system with little or no help from users.
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 its alleged proprietors were publicly identified by KrebsOnSecurity in 2021 after they inadvertently infected their computers with malware.
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 the defendants exposed their real-life identities after accidentally infecting their own systems with the malware.
Microsoft today released updates to plug at least 121 security holes in its Windows operating systems and software, including one vulnerability that is already being exploited in the wild. Eleven of those flaws earned Microsoft's most-dire "critical" rating, meaning malware or malcontents could exploit them with little to no interaction from Windows users.
Many successful phishing attacks result in a financial loss or malware infection. But falling for some phishing scams, like those currently targeting Russians searching online for organizations that are fighting the Kremlin war machine, can cost you your freedom or your life.
A clever malware deployment scheme first spotted in targeted attacks last year has now gone mainstream. In this scam, dubbed "ClickFix," the visitor to a hacked or malicious website is asked to distinguish themselves from bots by pressing a combination of keyboard keys that causes Microsoft Windows to download password-stealing malware.
One of the most notorious providers of abuse-friendly "bulletproof" web hosting for cybercriminals has started routing its operations through networks run by the Russian antivirus and security firm Kaspersky Lab, KrebsOnSecurity has learned.
The FBI joined authorities across Europe last week in seizing domain names for Cracked and Nulled, English-language cybercrime forums with millions of users that trafficked in stolen data, hacking tools and malware. An investigation into the history of these communities shows their apparent co-founders quite openly operate an Internet service provider and a pair of e-commerce platforms catering to buyers and sellers on both forums.
The FBI and authorities in The Netherlands this week seized a number of servers and domains for a hugely popular spam and malware dissemination service operating out of Pakistan. The proprietors of the service, who use the collective nickname "The Manipulaters," have been the subject of three stories published here since 2015. The FBI said the main clientele are organized crime groups that try to trick victim companies into making payments to a third party.
In January 2022, KrebsOnSecurity identified a Russian man named Mikhail Matveev as "Wazawaka," a cybercriminal who was deeply involved in the formation and operation of multiple ransomware groups. The U.S. government indicted Matveev as a top ransomware purveyor a year later, offering $10 million for information leading to his arrest. Last week, the Russian government reportedly arrested Matveev and charged him with creating malware used to extort companies.
Many GitHub users this week received a novel phishing email warning of critical security holes in their code. Those who clicked the link for details were asked to distinguish themselves from bots by pressing a combination of keyboard keys that causes Microsoft Windows to download password-stealing malware. While it's unlikely that many programmers fell for this scam, it's notable because less targeted versions of it are likely to be far more successful against the average Windows user.
An old but persistent email scam known as "sextortion" has a new personalized touch: The missives, which claim that malware has captured webcam footage of recipients pleasuring themselves, now include a photo of the target's home in a bid to make threats about publishing the videos more frightening and convincing.
The Russia-based cybercrime group dubbed "Fin7," known for phishing and malware attacks that have cost victim organizations an estimated $3 billion in losses since 2013, was declared dead last year by U.S. authorities. But experts say Fin7 has roared back to life in 2024 -- setting up thousands of websites mimicking a range of media and technology companies -- with the help of Stark Industries Solutions, a sprawling hosting provider is a persistent source of cyberattacks against enemies of Russia.
Law enforcement agencies in the United States and Europe today announced Operation Endgame, a coordinated action against some of the most popular cybercrime platforms for delivering ransomware and data-stealing malware. Dubbed "the largest ever operation against botnets," the international effort is being billed as the opening salvo in an ongoing campaign targeting advanced malware "droppers" or "loaders" like IcedID, Smokeloader and Trickbot.
The U.S. Department of the Treasury today unveiled sanctions against three Chinese nationals for allegedly operating 911 S5, an online anonymity service that for many years was the easiest and cheapest way to route one's Web traffic through malware-infected computers around the globe. KrebsOnSecurity identified one of the three men in a July 2022 investigation into 911 S5, which was massively hacked and then closed ten days later.
Last week, the United States joined the U.K. and Australia in sanctioning and charging a Russian man named Dmitry Yuryevich Khoroshev as the leader of the infamous LockBit ransomware group. LockBit's leader "LockBitSupp" claims the feds named the wrong guy, saying the charges don't explain how they connected him to Khoroshev. This post examines the activities of Khoroshev's many alter egos on the cybercrime forums, and tracks the career of a gifted malware author who has written and sold malicious code for the past 14 years.
Malicious hackers are targeting people in the cryptocurrency space in attacks that start with a link added to the target’s account at Calendly, a popular free calendar application for scheduling appointments and meetings. The attackers impersonate established cryptocurrency investors and ask to schedule a video conference call. But clicking the meeting link provided by the scammers prompts the user to run a script that quietly installs malware on macOS systems.