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The SOC Files: ScreenConnect masked as freeware. An inside look at a large

Introduction To access compromised systems, threat actors frequently abuse legitimate remote monitoring tools. At first glance, these utilities rarely raise red flags: they are signed with valid digital certificates, often allowlisted under corporate IT policies, and fully supported by OS vendors. However, they grant attackers the ability to harvest data from target devices, drop malware, and move laterally across the network. During a recent investigation engagement, the Kaspersky Managed Detection and Response (MDR) team discovered the ScreenConnect remote access tool being leveraged to deploy and execute an AsyncRAT payload. A deep dive into this single incident unraveled a massive campaign distributing malicious installer archives hosted on spoofed websites. These installers masquerade as popular software like OBS Studio, DNS Jumper, DS4Windows, Bandicam, and others. In total, we uncovered more than 90 domain names localized across 10 languages. The malicious archives bundle a legitimate, signed Microsoft install.exe binary alongside a rogue install.res.1033.dll library. It is loaded onto the device via DLL sideloading and deploys the ScreenConnect service, which awaits further instructions from the threat actors. As a result, what initially appeared to be an isolated ScreenConnect incident served as the starting point for a full investigation into the threat actor’s C2 infrastructure. Every spoofed site we uncovered followed the exact same playbook: dropping a hidden ScreenConnect remote administration service under the guise of a legitimate software installer. This allowed the attackers to maintain control over compromised endpoints, with victims ranging from individual users to organizations. We continue to break down complex, multi-stage incidents like this in our ongoing The SOC Files series. In this post, we take a deep dive into the technical execution of the ScreenConnect attack and analyze the broader infrastructure under the threat actor’s control. Initial incident investigation The investigation was triggered by an alert from Kaspersky MDR, which flagged the creation and execution of suspicious PowerShell and VBS scripts spawned by a ScreenConnect process. About ScreenConnect ScreenConnect is a legitimate remote management utility. Kaspersky solutions detect it as not-a-virus:HEUR:RemoteAdmin.MSIL.ConnectWise.gen. ScreenConnect was running as an Access-type service — enabling direct remote connectivity — with the server explicitly passed via the command line: Once running, ScreenConnect created and executed a PowerShell script named Fj5NmEsp9EuKrun.ps1 : Below is an excerpt from the contents of the script: This script configures Microsoft Defender exclusions for the following objects: - All disks in the system: C:\, D:\, and others - All root directories on the C:\ drive, as well as the C:\Users\Public directory RegAsm.exe process Additionally, the script disables User Account Control (UAC) prompts by setting the ConsentPromptBehaviorAdmin registry parameter to 0. Following this setup, the ScreenConnect service goes on to create a VBScript file: The installer_method3_stream.vbs script creates five files in the C:\Users\Public directory (msgbox.txt , secret_bytes.txt , 1.vb , cap.ps1 , and script.vbs ) and immediately triggers their execution by launching script.vbs . This script terminates all active powershell.exe processes to cover its tracks and executes cap.ps1 in a hidden window. cap.ps1 reads the contents of the secret_bytes.txt file, extracts sequences matching the [SXX- pattern, and converts XX from hexadecimal representation to a byte. It then uses a 0xA7 XOR key to decrypt each byte and inverts the bit order. The resulting byte array yields a fully formed PE binary, which is then reflectively loaded into the CLR. Within the loaded assembly, the ConsoleApp1.Module1 type contains a static method named Run . The script uses reflection (Reflection.BindingFlags ) to resolve a reference to this method and invoke it. The Run method executes a process hollowing technique (T1055.012), spawning a new RegAsm.exe process with the CREATE_SUSPENDED flag. The deobfuscated and decrypted PE image from secret_bytes.txt is then copied into its address space. As a result, the RegAsm.exe process no longer executes its original code, instead serving as a container for the injected .NET module — which, in this case, is the AsyncRAT remote access Trojan. To establish persistence, the malware schedules a task named MasterPackager.Updater: | 1 | "schtasks" /Create /TN "MasterPackager.Updater" /TR "wscript.exe "C:\Users\Public\script.vbs" " /SC MINUTE /MO 2 /F | This task triggers every two minutes, ensuring that script.vbs — and consequently the entire loader chain — executes even after a system reboot. Once the entire infection chain successfully executes, the RegAsm.exe process establishes a connection to the C2 domain mora1987[.]work[.]gd . How ScreenConnect entered the system A retrospective analysis of the incident allowed us to pinpoint the source of the ScreenConnect installation: a user-downloaded archive named obs-studio-windows-x64.zip . The archive was downloaded from hxxps://www.studioobs[.]com/ , a typosquatted domain mimicking the official site for OBS Studio, a popular open-source screen recording app. This site is present in search engine results; in this specific incident, the user landed on the malicious domain directly from a search query, a vector we analyze in more detail below. Clicking the download button for the supposedly legitimate software triggers a request to the following URL, from which the archive is fetched: | 1 | hxxps://fileget.loseyourip[.]com/obs-studio-windows-full/gVOMs5VZ9BtlcaM | The archive contains a legitimate, Microsoft-signed executable named install.exe (87603EA025623B19954E460ADD532048), renamed to masquerade as the OBS Studio installer, along with a malicious library named install.res.1033.dll . Additionally, the archive includes an Assets folder containing both a copy of the actual software being impersonated and the ScreenConnect utility. The complete file structure of the archive is organized as follows: When OBS-Studio-Installer.exe is executed, it loads install.res.1033.dll via DLL sideloading. This library contains the instructions required to install both ScreenConnect and OBS Studio. The deployment relies on native Windows utilities (msiexec.exe ), but the attackers renamed the standard MSI packages to look like DLL files: Assets\x86\Data\vcredist_x64.dll : ScreenConnect installerAssets\x86\Data\vcredist_x86.dll : OBS Studio installer The contents of the vcredist_x64.dll MSI package are shown below: The Windows Installer is launched to install ScreenConnect silently in the background without requiring a system reboot: | 1 | msiexec.exe /i "C:\Temp\OBS-Studio-Windows-x64\Assets\x86\vcredist_x64.dll" /qn /norestart | Once the installation wraps up, a new service named Microsoft Update Service is created. The command line for this service explicitly defines the connection server as r[.]servermanagemen[.]xyz . Meanwhile, the MSI package for the actual OBS Studio software runs using a standard graphical user interface. Expanding the investigation The attackers’ reliance on the legitimate install.exe binary provided a crucial pivot point for our broader investigation. We discovered that this specific file was being deployed in the wild under a variety of suspicious aliases, including: ds4windows.exe crosshairx_installer.exe obs-studio-installer.exe dns jumper.exe glary utilities pro.exe processhacker-2.39-setup.exe These file names indicate that the threat actor was disguising their ScreenConnect archives as popular utilities beyond OBS Studio. Among the fakes, we identified counterfeit installers for DS4Windows, DNS Jumper, Glary Utilities, and Process Hacker. Crucially, when we search for these utilities on major search engines, these fraudulent sites frequently appear at the very top of the organic search results. This indicates that the threat actor is actively leveraging SEO techniques to boost traffic to their landing pages. Spoofed software portals appearing in search engine results For example, here is how the fraudulent download portal for DNS Jumper looks: On this page, the download button directs users to the following address: | 1 | hxxps://direct-download.giize[.]com/dns-jumper/iopbsr4hymbo7nfa1q7j | Just like the OBS Studio variant, this drops an archive onto the victim’s device with an identical structure: a renamed legitimate install.exe file, a sideloaded library, and an Assets directory containing the promised software packaged alongside ScreenConnect. Other fraudulent websites that appear in search engine results when querying the corresponding software are designed in a similar fashion. Spoofed websites used to distribute ScreenConnect Notably, the vast majority of the fraudulent sites we uncovered are localized into English, Russian, and Chinese. In several instances, the pages were also translated into German, French, Spanish, Arabic, and other languages. This multi-language support underscores the global footprint of the campaign, targeting a broad user base across multiple regions. Fake domain infrastructure To distribute ScreenConnect disguised as freeware, the threat actor spun up an extensive network of domain names mapped across three IP addresses. We have categorized these into two distinct infrastructure clusters. Cluster 1: 162.216.241[.]242 and 198.23.185[.]81 | 1 2 3 4 5 | ``` 162.216.241[.]242 Country: United States Org name: Dynu Systems Incorporated ``` | The connection graph below illustrates the campaign websites tied to IP address 162.216.241[.]242 , which hosts the previously mentioned www[.]studioobs[.]com domain. Looking into the registration dates for the domains on this IP, we found that the threat actor initially attempted to disguise their sites as various gaming portals: Subsequently, starting in January 2026, they shifted strategy and began registering fake domains designed to mimic popular freeware: In this specific branch of the ScreenConnect campaign, the malicious archives are hosted on fileget.loseyourip[.]com . Notably, the download resource is hosted on a completely separate provider: | 1 2 3 4 5 | ``` 198.23.185[.]81 Country: United States Org name: NOHAVPS LLC ``` | Our analysis of this second IP address revealed that it also hosts additional resources tied to the campaign, including fake gaming sites and supplementary download links: Cluster 2: 2.59.134[.]97 | 1 2 3 4 5 | ``` 2.59.134[.]97 Country: Germany Org name: dataforest GmbH ``` | Below is an infrastructure graph showing this IP address and its hosted domains. Notably, unlike the previous case, this address also hosts direct-download.giize[.]com , a resource used to store distributed malicious archives. 2.59.134[.]97 were registered between October 2025 and March 2026. The chart below shows the volume of fraudulent websites created month by month: Breakdown of ScreenConnect delivery sites by theme, August 2025 through March 2026 (download) C2 infrastructure analysis In total, we identified dozens of different archives distributed across this campaign. All of them share a uniform file structure, containing the malicious install.res.1033.dll library and the ScreenConnect MSI package located at Assets\x86\vcredist_x64.dll . In some instances, the ScreenConnect installation package also bundles a CAB archive. This archive contains a system.config XML file, which defines the connection address for the ScreenConnect C2 server: By analyzing these ScreenConnect installations, we uncovered additional C2 addresses, which are mapped out in the following graph: The next graph illustrates the AsyncRAT command-and-control infrastructure: Based on the registration dates of the C2 domains, we can determine that the campaign was launched in October 2025 and paused at the end of March. However, at the time of publication, many of the landing pages remain accessible via search engine results. Takeaways Investigating a single case of AsyncRAT delivered via ScreenConnect allowed us to uncover a massive, multi-domain, multi-language infrastructure designed to distribute a hidden installer for this software and further advance the attack. The threat actor disguises ScreenConnect as popular utilities and distributes it through fraudulent websites that mimic official product pages. The attackers leverage search engine optimization techniques to push these sites to the top of search results in engines like Google and Bing. This attack chain targets both everyday consumers downloading free software from the internet and corporate networks, where remote access tools are frequently allowlisted and granted elevated privileges. The potential objective of the campaign is to steal credentials en masse and gain unauthorized access to systems for subsequent resale on dark web marketplaces. To mitigate the risks associated with this threat, we recommend implementing the following security measures: - Enforce strict software installation controls: application allowlisting and blocking MSI package execution from untrusted sources - Continuously monitor for the creation of new remote administration services and scheduler tasks - Filter outbound traffic to unknown domains and IP addresses - Regularly train users on safe downloading practices - Verify the authenticity of all software sources For enterprise users, credential monitoring is a critical mitigation strategy against the risks detailed in this article, as a leaked account or compromised system access frequently serves as a vector for subsequent attacks on the organization. Kaspersky Digital Footprint Intelligence provides continuous data monitoring across open and dark web sources, enabling security teams to respond proactively to potential threats. Detection by Kaspersky solutions Kaspersky Managed Detection and Response detects the malicious activity described in this post using the following indicators of attack: - ScreenConnect service creation with suspicious parameters 123456789101112131415logsource:product: windowscategory: securitydetection:selection_access:EventID: 4697Service File Name|contains:- 'e=Access'- 'ClientService.exe'selection_support:EventID: 4697Service File Name|contains:- 'e=Support'- 'ClientService.exe'condition: selection_access or selection_support - Anomalous child processes being spawned by the ScreenConnect service 1234567891011121314151617181920logsource:product: windowscategory: process_creationdetection:selection:ParentImage|endswith:- '\\ScreenConnect.ClientService.exe'- '\\ScreenConnect.WindowsClient.exe'- '\\ScreenConnect.WindowsBackstageShell.exe'- '\\ScreenConnect.WindowsFileManager.exe'Image|endswith:- '\\powershell.exe'- '\\cmd.exe'- '\\net.exe'- '\\schtasks.exe'- '\\sc.exe'- '\\msiexec.exe'- '\\mshta.exe'- '\\rundll32.exe'condition: selection Additionally, Kaspersky products detect the malware covered in this post under the following verdicts: - Trojan.Win64.DLLhijack.* - Trojan.VBS.Agent.* - Trojan.PowerShell.Agent.bav - Trojan.JS.SAgent.sb Endpoint malicious activity can be monitored using Kaspersky EDR Expert. Specifically, security teams should look for the execution of commands and scripts containing suspicious patterns, such as XOR operations used for command and data obfuscation by malware operating on the host. This activity is flagged by the suspicious_assembly_loading_into_powershell_via_reflection_amsi and xored_powershell_command_amsi rules. Additionally, persistence mechanisms involving the creation, modification, or utilization of scheduled tasks via the schtasks.exe utility are caught by the scheduled_task_create_from_public_directory_via_schtasks rule. Malicious code injection into the RegAsm.exe process — leveraged by attackers to masquerade execution behind a trusted system component — is detected via the code_injection_to_unusual_process rule. To visualize the stages of the attack, security teams can utilize Kaspersky Cloud Sandbox on the Threat Intelligence portal. For instance, this tool allows defenders to map out the entire deployment and payload execution chain originating from the initial VBS dropper. Furthermore, the Kaspersky Threat Intelligence portal supports searching and graphing the connections between malicious domains and files involved in this campaign, as demonstrated in our adversary infrastructure analysis section. Finally, the Similarity engine within Kaspersky Threat Analysis profiles file contents to hunt down samples resembling the original threat, helping organizations identify new or previously undetected malicious objects. Indicators of compromise Loaders B32810973132D11AFD61CCEE222BBB79 5B7E1FE55BD7B5EA54BD4ED1677E5A26 9A9CCD8B0E5D05F4EE77667B024844DB 0EEE9BAD07E22415439E854657FA1366 8F4E8B680D3E8D3F5AC39BD72882F713 Malicious library: install.res.1033.dll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syncRAT C2 Fake websites addresses ds4windows[.]io direct-download[.]giize[.]com tmodloader[.]org tmodloader[.]app ds4windows[.]net losslessscaling[.]app processhacker[.]dev steamtools[.]pro dnsjumper[.]app free-download[.]camdvr[.]org defendercontrol[.]org dns-jumper[.]com cpuz[.]app processhacker[.]org processhacker[.]app steamtools[.]cc cpuz[.]pro wallpaper-engine[.]app processhacker[.]net antimicrox[.]net defendercontrol[.]app tmodloader[.]pro dnsjumper[.]io bandicam[.]app mgba[.]app dnsjumper[.]pro ferdium[.]app ds4windows[.]pro lossless-scaling[.]online defender-control[.]com gom-player[.]app defendercontrol[.]pro lossless-scaling[.]download antimicrox[.]pro mgba[.]pro lossless-scaling[.]app losslessscaling[.]pro mgba[.]dev tmodloader[.]download tmod-loader[.]com defendercontrol[.]download ferdium[.]pro deadreset[.]com gom-player[.]net crosshairx[.]pro libreoffice[.]pro studioobs[.]com studio-obs[.]net crosshairxv2[.]com km-player[.]com corel-draw[.]net glary-utilities[.]com download-full-version[.]ooguy[.]com crosshair-x[.]com kms-tools[.]com studio-obs[.]com crosshairx[.]net clair-obscur-33[.]com vlc-player[.]net arksurvival-ascended[.]com elden-ringnightreign[.]com ready-ornot[.]com arma-reforger[.]com crusader-kings[.]com crosshairx2[.]com mediaplayerclassic[.]net bandizip[.]pro obs-studio[.]site ovr-advanced-settings[.]com studio-obs[.]pro vlc-media[.]com clair-obscur-33[.]town ovr-toolkit[.]com crusader-kings[.]church bandizip[.]net apexlegends[.]org obs-studio[.]pro vlc-media[.]net crosshairx[.]site monster-hunterwilds[.]com km-player[.]pro mediaplayerclassic[.]pro kms-tools[.]net fernbus-simulator[.]com studioobs[.]pro bandicam[.]cc crystaldiskmark[.]cc crystaldiskmark[.]io crystaldiskmark[.]dev crystaldiskmark[.]app crystaldiskmark[.]pro bandicam[.]io Fake domain infrastructure fileget.loseyourip[.]com file-download-crosshairx.giize[.]com all-toll-free.loseyourip[.]com mpc-update.giize[.]com all-toll-free.publicvm[.]com 198.23.185[.]81 direct-download.giize[.]com ScreenConnect C2 servermanagemen[.]xyz 185.254.97[.]249 r.manage-server[.]xyz 45.145.41[.]205 winservec[.]net manageserver[.]xyz cloudsynn[.]com pingserv[.]pro ehostservers[.]xyz serverdnsplan[.]net pingpanl[.]pro managedevice[.]xyz edgeserv[.]ru The SOC Files: ScreenConnect masked as freeware. An inside look at a large-scale campaign

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