Windows | Breaking Cybersecurity News | The Hacker News

Between November 2025 and March 2026, the Dutch security firm Eye Security pushed more than 2 million updates to computers it did not own to switch off a background updater that it said could have allowed an outsider to take over the machine. The updater belongs to Time4Popcorn , an abandoned copy of Popcorn Time, a free app that streamed pirated films and TV over BitTorrent. Popcorn Time was popular about a decade ago, and the original shut down in 2014, but several copies kept running under the same name. A separate, legal project that took the Popcorn Time name in early 2025 is unrelated to it. Eye Security, which monitors client networks for threats, found the updater during a routine threat hunt: a program called Updater.exe on one client's laptop kept trying to reach a web address that was no longer registered. The firm registered the address itself to see what would connect, and about 50 requests a second poured in. It later laid out the operation, which it named ...

Diplomatic organizations in Central Asia have been targeted by a sophisticated new Unified Extensible Firmware Interface (UEFI) bootkit called BlackX . The activity, which singled out diplomatic entities in Tajikistan, Uzbekistan, and Turkmenistan in early 2026, is suspected to be orchestrated by a China-linked state-sponsored hacking group known as APT41 , Kaspersky said in a technical report published this week. The primary objective behind deploying the malware is to undermine Microsoft Windows startup defenses, along with third-party security solutions, while maintaining long-term, covert access to compromised devices. Notably, BlackX is assessed to be an updated version of BlackLotus , a notorious bootkit that was first observed being advertised on cybercrime forums in late 2022, before its existence was officially confirmed by ESET in March 2023. BlackLotus is designed to exploit a now-patched Secure Boot bypass vulnerability tracked as CVE-2022-21894 (CVSS score: 4.4...

A flaw in the OpenCode AI coding agent allowed a malicious or hijacked MCP server to run code on a developer's Windows or WSL machine when the developer signed in. OpenCode connects to MCP (Model Context Protocol) servers to add outside tools, and such code would run with the developer's own access. Anomaly , the company behind OpenCode, fixed the flaw in  version 1.18.33  on September 28. It did not request a CVE or publish a security advisory, so vulnerability scanners will not flag the builds still at risk: 1.0.137 through 1.18.32. During that sign-in, the server itself supplies the web address the user is sent to, an OAuth "authorization endpoint." On Windows and WSL, OpenCode handed that address to a helper that opens it in a browser. The helper built a PowerShell command around the address without escaping it, so an address written to carry a PowerShell command would run that command. The browser step runs only when a developer starts the sign-in, by ru...

Attackers repeatedly changed the files that AOMEI Backupper fetches from the vendor's own update servers, in windows of five to ten minutes at a time between May and July 2026, so that any copy of the Windows backup program that checked for an update during one of those windows would download and run a backdoor. Google Threat Intelligence Group, Mandiant , and  ManageEngine's Threat Analysis Lab , which disclosed the campaign this week, say AOMEI has reported fixing its servers, but that fix does not remove the backdoor from machines that were already hit. AOMEI Backupper is Windows backup and disk-cloning software made by AOMEI Technology, a vendor registered in Hong Kong. Like the company's remote-desktop tool AnyViewer, it runs background services that regularly check AOMEI's servers over HTTPS for software updates and promotional pop-ups. Two files drive that check. One, down_html.ini, names the update package to download and the checksum the program uses to ...

Security researchers ran their own code inside a protected part of Windows that is meant to stay sealed off even when the rest of the computer is taken over. The protected area is a VBS enclave , an isolated slice of memory the operating system uses to guard secrets, and the one they broke into handles passwords for a Windows anti-phishing feature. The work was done in a lab as a proof of concept, has not been seen in real attacks, and Microsoft fixed the flaw in its September 8, 2026 update. The flaw is tracked as  CVE-2026-83498 . Microsoft rates it an elevation-of-privilege issue, Critical, with a CVSS score of 7.8, and says it has not been exploited and was not publicly known before the fix. Microsoft also says it found the same issue internally. The research, by the security firm  Doyensec , was published October 13, more than a month after the patch. A VBS enclave is a signed library that a normal Windows program loads but cannot read or change once it is runnin...

Microsoft on Tuesday shattered its own Patch Tuesday record by shipping patches for a whopping 1,413 vulnerabilities , including one that it said has come under active exploitation. These include 1,102 flaws in Windows, 134 in Office, 61 in Developer Tools, 36 in SharePoint Server, and 22 in SQL Server. Of these, more than 670 relate to privilege escalation, followed by over 300 remote code execution flaws and 250 information disclosure flaws. Over 70 flaws are rated Critical in severity. "Hundreds of CVEs in a single release used to be the exception; now it's the baseline," Dustin Childs, head of Threat Awareness at the Zero Day Initiative (ZDI), said . "Is AI to blame? Partly. It's accelerating bug-hunting on both sides of the fence, so vendors are finding (and fixing) more flaws, and researchers are finding them faster too." "But AI isn't creating these bugs out of thin air; it's just shortening the time between a vulnerability existin...

The Computer Emergency Response Team of Ukraine (CERT-UA) has identified more than 100 compromised websites that have been injected with malicious JavaScript to serve an information-stealing malware called LunexStealer (aka Psychedelic Stealer). The activity, which was observed by the agency in September 2026, has been attributed to a threat cluster dubbed UAC-0277. It did not disclose who the victims of the campaign were or if any systems were successfully compromised as a result of these attacks. "When visiting such a site, users were shown a forged Cloudflare verification page that, under the pretext of confirming the visitor is human, prompted them to execute a command," CERT-UA said in an advisory. "Executing the command caused a malicious MSI package to be downloaded and installed from a remote server (the ClickFix technique)." The attacks also make use of the EtherHiding technique to retrieve the domain name of the resource from which the fake verif...

Government and policy organizations across Asia have become the target of a new campaign orchestrated by a China-nexus threat actor. The activity, which has targeted government and policy organizations in Taiwan, India, the Philippines, Cambodia, Pakistan, Thailand, and Myanmar, involves the deployment of a previously undocumented backdoor codenamed Antino. Cisco Talos is tracking the cluster under the moniker UAT-11587 . The threat actor was first detected in September 2025 in connection with a spear-phishing campaign directed against Taiwan's academic, think tank, and civil society policy community. Since then, attacks linked to the intrusion set have expanded to target 16 entities across eight Asian countries. "Antino is a Rust-compiled Windows backdoor that supports host reconnaissance, shell and PowerShell execution, file transfer, in-memory shellcode loading and persistence," security researcher Ashley Shen said . "Its native command-and-control channel ...

Microsoft has warned of phishing campaigns distributing an installer for the MSP360 Remote Monitoring and Management (RMM) software under the guise of meeting invitations, PDF-themed lures, software update prompts, and other social-engineering content. "Once executed, the legitimate MSP360 installer, distributed under a deceptive file name established remote management access on affected devices and enabled threat actors to gain an initial foothold using trusted administrative software," the Microsoft Security Research team said . The initial foothold is then used to download and install a ConnectWise ScreenConnect client, offering threat actors a redundant remote-access channel to compromised endpoints. The access is then abused to deliver additional tools and carry out information collection and credential-access operations. The activity has not been attributed to any known threat actor or group. The multi-stage intrusion chain, which the Windows maker detected in Ju...

Russian state hackers known as Star Blizzard have been using fake event invitations to trick people into installing a backdoor on their Windows computers, according to Microsoft. The campaigns, aimed at people and organizations tied to Ukraine, have affected more than 100 organizations since January, mostly in the U.S. and U.K. At least one computer was infected, but the number of breached organizations has not been disclosed. Security agencies in the U.S., U.K., Australia, Canada and New Zealand  said in December 2023  that Star Blizzard almost certainly works under Center 18 of Russia's Federal Security Service (FSB). The group has long stolen email passwords by posing as people its targets know. By 2023, it had already used  fake conference and event invitations  as bait, often exchanging messages with a target before sending a malicious link. Microsoft counted at least 13 larger campaigns this year, each with tens to hundreds of emails, on top of ...

The Psychedelic Stealer malware distributed via compromised Ukrainian websites using ClickFix-style Cloudflare verification checks is part of a wider malware-as-a-service (MaaS) platform called Lunex . The new findings come from Ontinue, which described the activity as a four-stage attack chain aimed at targeting Ukrainian-speaking users. "The attack chain begins with a fake CAPTCHA page and culminates in the deployment of a fully-featured C2 agent," Ontinue threat researcher Rhys Downing said in a technical report. "The stealer extracts credentials and data from seven Chromium-based browsers, exfiltrates cryptocurrency wallets, and establishes persistent remote filesystem access through a PowerShell-based Native Messaging Host installed within the victim's browser." The infection makes use of bogus MSI installers delivered via ClickFix to trigger a series of actions, including delivering a loader dubbed LunexLoader that's designed to bypass User Ac...

The "third-party[.]com" domain, commonly used as a documentation placeholder, has been observed serving a ClickFix lure to Windows browsers while displaying a harmless decoy to other users. "third-party[.]com has been a generic documentation placeholder for years, the same role example.com plays," Manifold Security's Head of Research, Ax Sharma, said . "Unlike 'example[.]com,' third-party[.]com is not IANA-reserved . Anyone could register it, and someone did. Every doc, test, and skill that hard-coded it now points readers at attacker infrastructure." As of writing, the domain has been marked as malicious and unsafe on both VirusTotal and Google's Safe Browsing list . ClickFix is a social engineering attack technique in which either malicious or legitimate-but-compromised websites display error messages, browser alerts, or CAPTCHA verification prompts, tricking users into copying and executing hidden commands via the Windows Run d...

A Windows malware called CLOSEDQUORUM is built to take orders from a vote of up to four AI models instead of an attacker's server, Cisco Talos said on September 22. The models can choose to steal Windows credentials, saved browser passwords, and crypto wallet data. Talos has not seen this setup work from start to finish, and the public version of the malware does not work as it is. Talos found the malware with  CAIRN , an open-source tool it released the same day to hunt for malware that uses AI services. The malware is at least three months old, because Talos's analysis of the code is dated June 17, 2026. The researchers did not describe how the malware would get onto a victim's computer. It said clues in the code tied the developer to criminal forum posts about carding, the trade in stolen card data, dating to 2025. How the AI Vote Works Malware usually takes orders from a command-and-control (C2) server that the attacker runs. CLOSEDQUORUM instead asks up t...

A zero-day proof-of-concept tool that stops Microsoft Defender from installing platform and signature updates by filling all available disk space was  published on GitHub  on September 19. The tool, called BigDiskBuster , has no patch, no CVE, and no Microsoft advisory. Its author, Abdelhamid Naceri, is a former Microsoft security researcher whose earlier Defender exploits were used in attacks. When updates are blocked, Defender keeps running, but its detection content grows stale. The researcher's screenshot shows Defender returning a generic Windows error when trying to update, but whether the failure raises an automatic alert is not clear from the proof-of-concept alone. Naceri said he was dismissed from Microsoft's Security Response Center in 2024 and has been releasing exploits without coordinating with the company since April. His first three Defender tools — BlueHammer, RedSun, and UnDefend — were all  exploited in live intrusions  before Microsoft...

A fake LastPass Authenticator installer offered on GitHub installs a Windows kernel driver that shuts off antivirus and other security software before a password stealer runs if a victim downloads and runs it, researchers at LastPass and Delphos Labs said on September 17. Microsoft's own hardware-compatibility program signs the driver, scored zero detections on VirusTotal when researchers checked it in August, and was not on Microsoft's list of blocked drivers. LastPass says none of its own systems, services, or customer vaults were touched, and that the attackers only borrowed its name. The lure is a fake GitHub page (github.com/LastPass-Authenticator) that ranks in search results for terms like "LastPass Authenticator download" and looks like a real LastPass product page. Clicking the download button sends the visitor through several GitHub pages to an attacker server, which serves a large ZIP file. The real LastPass Authenticator comes from lastpass.com and ...

Cybersecurity researchers have disclosed details of a new campaign dubbed TASK#STOMP that delivers a PowerShell backdoor designed to harvest sensitive data from compromised hosts. The backdoor "automatically harvests and exfiltrates business documents, watches the filesystem for new files in real time, steals Wi-Fi passwords and clipboard contents, takes screenshots, and accepts arbitrary remote commands through two redundant, token-authenticated C2 servers," Securonix researchers Akshay Gaikwad and Aaron Beardslee said in a report shared with The Hacker News. The starting point of the infection chain is the use of "wscript.exe" to execute an encoded Visual Basic Script (VBScript) file staged on the victim's desktop ("95c9050t66.vbs"). The exact initial access pathway used to deliver the payload is unclear, although it's possible that it may have been via email-based phishing or social engineering. By giving it a completely random file nam...

Microsoft has released fixes for a maximum-severity security flaw in Azure AI Foundry that could be exploited to achieve privilege escalation. No customer action is required. The vulnerability, tracked as CVE-2026-85889 , carries a CVSS score of 10.0. "Missing authentication for critical function in Azure AI Foundry allows an unauthorized attacker to elevate privileges over a network," Microsoft said in a Thursday advisory. Azure AI Foundry, also called Microsoft Foundry, is an enterprise platform designed to build, deploy, and manage generative artificial intelligence (AI) applications and agents. The Windows maker credited security researcher Rémy Marot (@R_Marot) for discovering and reporting the flaw. There is no evidence that the issue has been exploited in the wild. Also patched by Microsoft in recent days are a number of other critical flaws -

Cybersecurity agencies in the United States, the United Kingdom, and the Netherlands have detailed a Windows malware that they say Iran's intelligence service uses to spy on dissidents, journalists, and activists around the world. The malware is controlled via the Telegram messaging app and can copy a target's emails and chat messages, take screenshots, and activate the microphone to record audio. The FBI calls it HEAVYGRAM , and the U.K.'s National Cyber Security Center (NCSC) calls it CHOSEN BRICK . The  joint advisory  was published on September 15 by the NCSC , the FBI, and the Netherlands' intelligence service, the AIVD. The FBI also released an  updated analysis  of the malware that expands on a  March 2026 alert , the first to describe the campaign, with more technical detail and new indicators of compromise. The FBI attributes the malware to Iran's Ministry of Intelligence and Security (MOIS), the country's main intelligence agency, and dates th...

Cybersecurity researchers have disclosed details of a multi-platform campaign that uses the Message Queueing Telemetry Transport ( MQTT ) protocol as a communication channel to control Windows and Linux systems. The emerging malware family, codenamed BambooToken , is assessed to be active since at least February 2023 and put to use in attacks targeting organizations across Asia and South America. Activity linked to the malware has been detected as recently as July 2026. Lumen Black Lotus Labs said it discovered the previously undocumented malware on VirusTotal in early 2026, with evidence pointing to a skilled threat actor that has managed to stay undetected until now. The initial access vector used to deliver BambooToken remains undetermined. "The actor used Tendyron's 'OnKey' software to sideload agents into targeted machines," Black Lotus Labs said in a report shared with The Hacker News. "Tendyron creates hardware-based tokens employed in high-se...

Multiple espionage-motivated threat activity clusters have been found deploying a previously undocumented exploit kit called BlueMoon that chains together multiple vulnerabilities in Microsoft Windows and Google Chrome. The first in-the-wild use of BlueMoon has been attributed to the China-aligned state-sponsored group tracked as APT31 (aka Bronze Vinewood, Judgement Panda, JungleBamboo, PerplexedGoblin, RedBravo, TA412, Tide Castle, and Violet Typhoon) on August 28, 2026. "Within days, several other espionage-motivated clusters began using BlueMoon, the majority of which have a suspected China nexus," Proofpoint said in a report published today. "However, BlueMoon may not be exclusive to China-aligned actors, as some usage remains unattributed and there are also potentially more actors using the exploit kit." The exploit chain employs three vulnerabilities - CVE-2026-85046 , a type confusion in V8 in Google Chrome CVE-2026-87491 , an out-of-bounds...