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Ransomware is malicious software designed to block access to a computer system or encrypt data until a ransom is paid. This cyberattack is one of the most prevalent and damaging threats in the digital landscape, affecting individuals, businesses, and critical infrastructure worldwide. A ransomware attack typically begins when the malware infiltrates a system through various vectors such as phishing emails, malicious downloads, or exploiting software vulnerabilities. Once activated, the malware encrypts files using strong cryptographic algorithms, rendering them inaccessible to the legitimate owner. The attackers then demand payment, usually in cryptocurrency like Bitcoin, in exchange for the decryption key. Modern ransomware variants have evolved beyond simple file encryption. Some employ double extortion tactics, where attackers encrypt data, exfiltrate sensitive information, and threaten to publish it publicly if the ransom is not paid. This puts pressure on victims, particularly...

Threat actors are leveraging weaponized attachments distributed via phishing emails to deliver malware likely targeting the defense sector in Russia and Belarus. According to multiple reports from Cyble and Seqrite Labs , the campaign is designed to deploy a persistent backdoor on compromised hosts that uses OpenSSH in conjunction with a customized Tor hidden service that employs obfs4 for traffic obfuscation. The activity has been codenamed Operation SkyCloak by Seqrite, stating the phishing emails utilize lures related to military documents to convince recipients into opening a ZIP file containing a hidden folder with a second archive file, along with a Windows shortcut (LNK) file, which, when opened, triggers the multi-step infection chain. "They trigger PowerShell commands which act as the initial dropper stage where another archive file besides the LNK is used to set up the entire chain," security researchers Sathwik Ram Prakki and Kartikkumar Jivani said, adding...

Google's artificial intelligence (AI)-powered cybersecurity agent called Big Sleep has been credited by Apple for discovering as many as five different security flaws in the WebKit component used in its Safari web browser that, if successfully exploited, could result in a browser crash or memory corruption. The list of vulnerabilities is as follows - CVE-2025-43429 - A buffer overflow vulnerability that may lead to an unexpected process crash when processing maliciously crafted web content (addressed through improved bounds checking) CVE-2025-43430 - An unspecified vulnerability that could result in an unexpected process crash when processing maliciously crafted web content (addressed through improved state management) CVE-2025-43431 & CVE-2025-43433 - Two unspecified vulnerabilities that may lead to memory corruption when processing maliciously crafted web content (addressed through improved memory handling) CVE-2025-43434 - A use-after-free vulnerability that may ...

Federal prosecutors in the U.S. have accused a trio of allegedly hacking the networks of five U.S. companies with BlackCat (aka ALPHV) ransomware between May and November 2023 and extorting them. Ryan Clifford Goldberg, Kevin Tyler Martin, and an unnamed co–conspirator (aka "Co-Conspirator 1") based in Florida, all U.S. nationals, are said to have used the ransomware strain against a medical device company based in Tampa, Florida, a pharmaceutical company based in Maryland, a doctor's office based in California, an engineering company based in California, and a drone manufacturer based in Virginia. The Chicago Sun-Times first reported the indictment over the weekend, stating Martin and Co-Conspirator 1 were employed as ransomware threat negotiators for a company named DigitalMint at the time when these incidents took place. Goldberg was an incident response manager for cybersecurity company Sygnia. All three individuals are no longer working at the respective firms...

Microsoft has disclosed details of a novel backdoor dubbed SesameOp that uses OpenAI Assistants Application Programming Interface (API) for command-and-control (C2) communications. "Instead of relying on more traditional methods, the threat actor behind this backdoor abuses OpenAI as a C2 channel as a way to stealthily communicate and orchestrate malicious activities within the compromised environment," the Detection and Response Team (DART) at Microsoft Incident Response said in a technical report published Monday. "To do this, a component of the backdoor uses the OpenAI Assistants API as a storage or relay mechanism to fetch commands, which the malware then runs." The tech giant said it discovered the implant in July 2025 as part of a sophisticated security incident in which unknown threat actors had managed to maintain persistence within the target environment for several months. It did not name the impacted victim. Further investigation into the intrusio...