Latest cybersecurity reporting from selected sources.

Microsoft says GigaWiper combines at least 3 malware families into one modular tool

GigaWiper, also tracked as BLUERABBIT, is a destructive backdoor that combines multiple wiping and ransomware-like capabilities into a single operational platform. This blog analyzes how the malware incorporates code from several previously separate malware families and provides guidance to help defenders detect and defend against similar threats. The post GigaWiper: Anatomy of a destructive backdoor assembled from multiple malware appeared first on Microsoft Security Blog.

Cybersecurity researchers have flagged a new malware artifact generated using DeepSeek that constructed a novel attack path combining "unrealistic browser-malware concepts with a real browser capability" to turn it into a working ransomware technique that runs entirely inside the browser on both Windows and Android devices

A coordinated law enforcement operation, in partnership with private sector companies, including Bitdefender, Bitsight, ESET, and Microsoft, has resulted in the takedown of criminal infrastructure powering Amadey and StealC

DragonForce hid for months by routing malware traffic through Microsoft Teams infrastructure, masking C2 activity and evading network detection. DragonForce ransomware operators hit a major U.S. services firm and stayed hidden for one to two months by routing their command-and-control traffic through Microsoft’s own Teams relay servers. Symantec’s threat hunters tracked the custom backdoor they […]

DragonForce ransomware used a custom malware named 'Backdoor.Turn' to hide command-and-control traffic inside Microsoft Teams relay infrastructure. [...]

Microsoft on Tuesday said it disrupted a malware-signing-as-a-service (MSaaS) operation that weaponized the company's Artifact Signing system to deliver malicious code and conduct ransomware and other attacks, compromising thousands of machines and networks across the world

'Thousands' of US victims, including 12+ machines owned and operated by Redmond

Microsoft says it has disrupted a malware-signing-as-a-service (MSaaS) operation that abused the company's Artifact Signing service to generate fraudulent code-signing certificates used by ransomware gangs and other cybercriminals. [...]

Fox Tempest is a financially motivated threat actor operating a malware‑signing‑as‑a‑service (MSaaS) used by other cybercriminals, including Vanilla Tempest and Storm groups, to more effectively distribute malicious code, including ransomware. The post Exposing Fox Tempest: A malware-signing service operation appeared first on Microsoft Security Blog.

Fox Tempest, a financially-motivated threat group, allowed ransomware operators and other cybercriminals to slip malware-laced software past security controls. The post Microsoft disrupts cybercrime service that abused software verification systems en masse appeared first on CyberScoop.

Ransomware threat actors tracked as Velvet Tempest are using the ClickFix technique and legitimate Windows utilities to deploy the DonutLoader malware and the CastleRAT backdoor. [...]

High-volume phishing campaign delivers Phorpiex malware via malicious Windows Shortcut files

Ransomware attackers targeting a Fortune 100 company in the finance sector used a new malware strain, dubbed PDFSider, to deliver malicious payloads on Windows systems. [...]

Security boffins warn flaw is now being used for ransomware attacks against live networks Microsoft says attackers have already compromised "several hundred machines across a diverse set of organizations" via the React2Shell flaw, using the access to execute code, deploy malware, and, in some cases, deliver ransomware.…

An initial access broker tracked as Storm-0249 is abusing endpoint detection and response solutions and trusted Microsoft Windows utilities to load malware, establish communication, and persistence in preparation for ransomware attacks. [...]

Security pros explore whether infection-spoofing code can immunize Windows systems against attack Feature What's better, prevention or cure? For a long time the global cybersecurity industry has operated by reacting to attacks and computer viruses. But given that ransomware has continued to escalate, more proactive action is needed.…

Microsoft has revoked over 200 fraudulent code-signing certificates used in a ransomware campaign involving fake Teams installers by threat group Vanilla Tempest

Brazilian users have emerged as the target of a new self-propagating malware that spreads via the popular messaging app WhatsApp

Attackers are wielding the sophisticated modular malware while exploiting CVE-2025-29824, a previously zero-day flaw in Windows Common Log File System (CLFS) that allows attackers to gain system-level privileges on compromised systems.