All news with #malware tag

🔍 Google Threat Intelligence Group (GTIG) reports an operational shift from adversaries using AI for productivity to embedding generative models inside malware to generate or alter code at runtime. GTIG details “just-in-time” LLM calls in families like PROMPTFLUX and PROMPTSTEAL, which query external models such as Gemini to obfuscate, regenerate, or produce one‑time functions during execution. Google says it disabled abusive assets, strengthened classifiers and model protections, and recommends monitoring LLM API usage, protecting credentials, and treating runtime model calls as potential live command channels.

📱 Security researchers at Zscaler report a 67% year-on-year rise in Android-targeted malware after finding 239 malicious apps on Google Play that were downloaded 42 million times. The analysis covers more than 20 million mobile requests observed between June 2024 and May 2025 and highlights productivity and Tools apps as common vectors. Sectors such as manufacturing and energy were disproportionately targeted, with the energy sector seeing a 387% spike in mobile attacks.

🔒 A Zscaler report found 239 malicious Android apps on Google Play that were downloaded a combined 42 million times between June 2024 and May 2025, driven largely by adware, spyware, and banking trojans. Telemetry shows a 67% year-over-year increase in mobile-targeted malware, with adware now comprising roughly 69% of detections and spyware up 220% YoY. Zscaler highlights evolving strains such as Anatsa, Android Void, and Xnotice, and advises timely updates, strict app permissions, disabling unnecessary Accessibility access, and regular Play Protect scans.

🔐 Nikkei disclosed that unauthorized actors accessed employee Slack accounts after an employee's computer was infected with malware and credentials were stolen. The breach exposed the names, email addresses, and chat histories of 17,368 registered users. Nikkei discovered the incident in September, enforced mandatory password resets, and voluntarily notified the Personal Information Protection Commission, stating that journalist sources and reporting data were not compromised.

🔐 Microsoft Incident Response (DART) uncovered a covert backdoor named 'SesameOp' in July 2025 that leverages the OpenAI Assistants API as a command-and-control channel. The malware uses an obfuscated DLL loader, Netapi64.dll, and a .NET component, OpenAIAgent.Netapi64, to fetch compressed, encrypted commands and return results via the API. Microsoft recommends firewall audits, EDR in block mode, tamper protection and cloud-delivered Defender protections to mitigate the threat.

🛡️The Russian-linked threat group Curly COMrades abused Microsoft Hyper-V on Windows hosts to deploy a hidden, minimal Alpine Linux VM that hosted custom implants: CurlyShell (reverse shell) and CurlCat (reverse proxy). By using the Hyper-V Default Switch and naming the VM "WSL," outbound C2 traffic appeared to originate from the legitimate host IP, enabling evasion of host-based EDRs. The campaign — active since mid-2024 and observed by Bitdefender with help from the Georgian CERT — also employed PowerShell scripts for LSASS Kerberos ticket injection and Group Policy-based account creation, leaving few forensic traces. Organizations are advised to monitor unexpected Hyper-V activation, abnormal LSASS access or tampering, PowerShell GPO deployments, and to implement network-level inspection and layered defenses.

🔒 Microsoft’s Detection and Response Team (DART) detailed a novel .NET backdoor called SesameOp that leverages the OpenAI Assistants API as a covert command-and-control channel. Discovered in July 2025 during a prolonged intrusion, the implant uses a loader (Netapi64.dll) and an OpenAIAgent.Netapi64 component to fetch encrypted commands and return execution results via the API. The DLL is heavily obfuscated with Eazfuscator.NET and is injected at runtime using .NET AppDomainManager injection for stealth and persistence.

🛡️ A remote-access trojan named SleepyDuck, disguised as a Solidity extension on Open VSX, uses an Ethereum smart contract to deliver command-and-control instructions. The malicious package, downloaded over 53,000 times, activates on editor startup, when a Solidity file is opened, or when the compile command is run. On activation it collects system identifiers, creates a lock file for persistence, and polls an on-chain contract to update or replace its C2 endpoint. Open VSX has flagged the package and implemented security controls; developers should rely only on reputable publishers and official repositories.

🔐 Microsoft security researchers identified a new backdoor, SesameOp, which abuses the OpenAI Assistants API as a covert command-and-control channel. Discovered during a July 2025 investigation, the backdoor retrieves compressed, encrypted commands via the API, decrypts and executes them, and returns encrypted exfiltration through the same channel. Microsoft and OpenAI disabled the abused account and key; recommended mitigations include auditing firewall logs, enabling tamper protection, and configuring endpoint detection in block mode.

🦆 Researchers at Secure Annex warned of a malicious Open VSX extension, juan-bianco.solidity-vlang, that delivers a remote access trojan dubbed SleepyDuck. Originally published as a benign library on October 31, 2025, it was updated to a malicious release after reaching about 14,000 downloads. The extension triggers on opening a code editor window or selecting a .sol file, harvesting host details and polling an Ethereum-based contract to obtain and update its command server. It also contains fallback logic using multiple Ethereum RPC providers to recover C2 information if the domain is taken down; users should only install extensions from trusted publishers and follow vendor guidance.

🛡️ Microsoft DART researchers uncovered SesameOp, a novel .NET backdoor that leverages the OpenAI Assistants API as a covert command-and-control (C2) channel instead of traditional infrastructure. The implant includes a heavily obfuscated loader (Netapi64.dll) and a backdoor (OpenAIAgent.Netapi64) that persist via .NET AppDomainManager injection, using layered RSA/AES encryption and GZIP compression to fetch, execute, and exfiltrate commands. Microsoft and OpenAI investigated jointly and disabled the suspected API key; detections and mitigation guidance are provided for defenders.

🔒 Cybersecurity researchers CYFIRMA and independent analyst F6 have disclosed two active Android trojans—BankBot‑YNRK and DeliveryRAT—that harvest financial and device data from compromised phones. BankBot‑YNRK impersonates an Indonesian government app, performs device fingerprinting and anti-emulation checks, abuses accessibility services to steal credentials and automate transactions, and communicates with a command server. DeliveryRAT, promoted via a Telegram bot, lures Russian users with fake delivery and marketplace apps and delivers malware-as-a-service variants that collect notifications, SMS and call logs and can hide their launchers. Users should avoid untrusted APKs, review permissions, and keep devices updated—Android 14 reduces some accessibility-based abuses.

🔒 A Ukrainian man long accused of building and operating components of the Jabber Zeus banking trojan has been arrested in Italy and is now in U.S. custody. Prosecutors say 41-year-old Yuriy Igorevich Rybtsov, previously identified only by the handle MrICQ, was charged in a 2012 Nebraska indictment as a developer and notification handler for the group. Investigators allege Jabber Zeus used a custom ZeuS variant and a Leprechaun component to intercept credentials and bypass multi-factor protections, enabling large payroll thefts via recruited money mules.

🛡️ The Australian Signals Directorate (ASD) has issued a bulletin warning of ongoing attacks using a Lua-based implant dubbed BADCANDY to compromise unpatched Cisco IOS XE devices via CVE-2023-20198. ASD reports variations have been seen since October 2023 and estimates about 400 Australian devices were compromised since July 2025, with 150 infections in October. Operators are urged to apply patches, restrict public access to the web UI, and follow Cisco hardening guidance.

🛡️ Microsoft is adding a new scareware sensor to Edge that notifies Defender SmartScreen in real time to speed up indexing and global blocking of tech-support and full-screen scam pages. The sensor is included in Edge 142, disabled by default, and reports suspected scams immediately without sharing screenshots or extra data beyond SmartScreen’s usual telemetry. Edge’s local scareware blocker — introduced at Ignite 2024 and widely enabled since February — still warns users, exits full-screen, stops loud audio, shows a thumbnail, and offers an option to continue. Microsoft plans to enable the sensor for users who have SmartScreen enabled and will add more anonymous detection signals over time.

🛡️ Palo Alto Networks Unit 42 linked a suspected nation-state cluster (CL-STA-1009) to a new backdoor named Airstalk that abuses the AirWatch API (now Workspace ONE Unified Endpoint Management) as a covert command-and-control channel. The malware appears in PowerShell and more capable .NET variants and can capture screenshots, harvest browser cookies, history and bookmarks, and enumerate user files. Airstalk misuses MDM custom attributes as a dead-drop resolver and leverages the API blobs feature to exfiltrate large artifacts; some .NET samples were signed with a likely stolen certificate.

🔒 Russian authorities have arrested three individuals in Moscow accused of creating and operating the Meduza information‑stealing malware. Announced on Telegram by police general Irina Volk, investigators say the group developed and distributed Meduza via hacker forums around two years ago and offered it as a subscription-based service. The tool steals browser-stored credentials and cryptocurrency data and, since December 2023, can resurrect expired Chrome authentication cookies to facilitate account takeover. Authorities opened a criminal case after operators targeted an Astrakhan institution and seized confidential server data.

🔒 As October 2025 concludes, ESET Chief Security Evangelist Tony Anscombe reviews the month’s most significant cybersecurity developments and what they mean for defenders. He highlights that Windows 10 reached end of support on October 14 and outlines practical options for affected users and organizations. He also warns about info‑stealing malware spread through TikTok videos posing as free activation guides and summarizes Microsoft’s report that Russia, China, Iran and North Korea are increasingly using AI in cyberattacks — alongside China’s accusation of an NSA operation targeting its National Time Service Center.

🔍 Researchers at Koi Security uncovered a campaign, PhantomRaven, that has contaminated 126 packages in Microsoft's npm repository by embedding invisible HTTP URL dependencies. These remote links are not fetched or analyzed by typical dependency scanners or npmjs.com, making packages appear to have 0 Dependencies while fetching malicious code at install time. The attackers aim to exfiltrate developer credentials and environment details, and they also exploit AI hallucinations to create plausible package names.

📱Zimperium reports a sharp rise in Android apps abusing Host Card Emulation (HCE) to steal contactless payment card data across Eastern Europe. Researchers observed over 760 malicious APKs and 70+ command-and-control servers that capture EMV fields, respond to POS APDU commands, or forward requests to remote servers. Variants include data exfiltration to Telegram, relay toolkits, 'ghost-tap' real-time HCE manipulation, and fake payment apps impersonating Google Pay and regional banks. Users are advised to avoid sideloading APKs, restrict NFC permissions, run Play Protect, and disable NFC when not in use.