All news with #remote access trojan tag

📧 Volexity has linked a series of spear-phishing campaigns from June to August 2025 to a China-aligned actor tracked as UTA0388. The group used tailored, rapport-building messages impersonating senior researchers and delivered archive files that contained a benign-looking executable alongside a hidden malicious DLL loaded via search order hijacking. The distributed malware family, labeled GOVERSHELL, evolved through five variants capable of remote command execution, data collection and persistence, shifting communications from simple shells to encrypted WebSocket and HTTPS channels. Linguistic oddities, mixed-language messages and bizarre file inclusions led researchers to conclude LLMs likely assisted in crafting emails and possibly code.

🔒 Sekoia warns of a large-scale phishing campaign targeting hotel staff that uses ClickFix-style pages to harvest credentials and deliver PureRAT. Attackers impersonate Booking.com in spear-phishing emails, redirect victims through a scripted chain to a fake reCAPTCHA page, and coerce them into running a PowerShell command that downloads a ZIP containing a DLL-side‑loaded backdoor. The modular RAT supports remote access, keylogging, webcam capture and data exfiltration and persists via a Run registry key.

🔒 A large-scale phishing operation targeted Booking.com partner accounts and hotel staff, using impersonated emails and compromised hotel accounts to lure victims into running malicious commands. Attackers relied on redirection chains and the ClickFix social engineering tactic to execute PowerShell that delivered PureRAT. The remote access trojan enabled credential theft, screenshots and exfiltration, with stolen access sold or used to perpetrate payment fraud against guests.

🛡️ Proofpoint has identified a previously unknown cluster it calls UNK_SmudgedSerpent that targeted academics and foreign policy experts between June and August 2025. Attackers initiated benign, topical conversations and used think‑tank impersonation alongside an OnlyOffice‑styled link that led to health-themed domains harvesting credentials and delivering a ZIP with an MSI. The installer deployed remote monitoring and management tooling — notably PDQConnect and later ISL Online — and although email activity paused in early August, related infrastructure later surfaced hosting TA455-linked malware, leaving attribution unresolved.

🔐 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.

🛡️ Researchers at Microsoft disclosed a previously undocumented backdoor, dubbed SesameOp, that abuses the OpenAI Assistants API to relay commands and exfiltrate results. The attack chain uses .NET AppDomainManager injection to load obfuscated libraries (loader "Netapi64.dll") into developer tools and relies on a hard-coded API key to pull payloads from assistant descriptions. Because traffic goes to api.openai.com, the campaign evaded traditional C2 detection. Microsoft Defender detections and account key revocation were used to disrupt the operation.

🔒 Attackers are deploying a persistent backdoor using OpenSSH and a customized Tor hidden service to target defense-related organizations in Russia and Belarus. The Operation SkyCloak campaign uses weaponized ZIP attachments and LNK-triggered PowerShell stagers that perform sandbox evasion and write an .onion hostname into the user's roaming profile. Persistence is established via scheduled tasks that run a renamed sshd.exe and a bespoke Tor binary using obfs4, enabling SSH, SFTP, RDP and SMB access over Tor.

🔒 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.

🚨 Threat actors are targeting freight brokers and carriers with malicious emails and compromised load-board posts to deliver remote monitoring and management tools (RMM) such as ScreenConnect, NetSupport, and PDQ Connect. Once installed, attackers gain remote control to alter bookings, block notifications, harvest credentials, and impersonate carriers to reroute and physically steal high-value shipments. Proofpoint tracked dozens of campaigns since January, primarily in North America, exploiting social engineering and legitimate RMM functionality.

🔒 Security researchers at Gen Digital disclosed a targeted Kimsuky campaign that delivered a previously undocumented backdoor called HttpTroy, hidden inside a ZIP attachment masquerading as a VPN invoice. The multi-stage chain used a Golang dropper, a loader dubbed MemLoad and a DLL backdoor executed via a scheduled task named "AhnlabUpdate" to achieve persistence. HttpTroy provides extensive remote-control capabilities and communicates with a C2 server over HTTP, while employing layered obfuscation to hinder analysis and detection.

🔒 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.

🛡️Arctic Wolf reports that Chinese government-linked actors, tracked as UNC6384 and linked to the longer-running Mustang Panda cluster, conducted spear-phishing campaigns in September and October targeting diplomats in Hungary, Belgium, Serbia, Italy and the Netherlands by abusing a long-known Windows .LNK shortcut parsing flaw. The vulnerability allows command-line instructions to be concealed in .LNK whitespace so attackers can display decoy PDFs—such as an agenda for a European Commission meeting—while executing payloads that deploy the PlugX remote-access Trojan. Trend Micro and ZDI previously documented the issue (i.e., ZDI-CAN-25373, later CVE-2025-9491), but Microsoft has so far declined to fully patch it; Arctic Wolf advises blocking or disabling .LNK execution, monitoring for related binaries like cnmpaui.exe, and blocking C2 domains as interim mitigations.

🛡️ 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.

🔒 A China-linked threat group is exploiting a high-severity Windows .LNK zero-day (CVE-2025-9491) to deploy the PlugX remote-access trojan against European diplomatic targets. The campaign begins with spearphishing that delivers malicious shortcut files themed around NATO and European Commission events. Researchers at Arctic Wolf Labs and StrikeReady attribute the activity to UNC6384 (Mustang Panda) and report the operation has expanded beyond Hungary and Belgium to other EU states. With no official patch available, defenders are urged to restrict .LNK usage and block identified C2 infrastructure.

⚠️ Silent Push reports a surge in malicious use of AdaptixC2, an open-source adversarial emulation framework that researchers say is now being delivered by the CountLoader malware as part of active ransomware operations. Deployments accelerated after new detection signatures were released, and public incident reports show increased sightings across multiple intrusions. Analysts flagged the developer alias RalfHacker and issued indicators covering Golang C2 traffic and unknown C++/QT executables.

🔍 Security researchers at Varonis identified a modular remote access trojan named Atroposia, first seen on October 15 and promoted on underground forums. The toolkit includes encrypted C2 channels, hidden remote desktop takeover (HRDP Connect), credential and cryptocurrency wallet theft, DNS hijacking, vulnerability scanning and robust persistence. It is offered via subscription tiers and can be combined with services like SpamGPT and MatrixPDF to automate phishing and delivery. Recommended defenses include phishing reduction, timely patching, MFA enforcement and monitoring for post-compromise activity.