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Security Independently confirmed4 publishers 2 min read Published Updated

Attackers move the ClickFix paste into Windows Terminal to land a multi-stage intrusion chain

Microsoft's TerminalFix writeup shows the same fake CAPTCHA lure now feeding multi-line PowerShell into Windows Terminal, where it sideloads a signed binary, pulls payloads out of PNG files and leaves a reverse tunnel behind.

The Watch · Security desk

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What happened

  • A fake Cloudflare Turnstile overlay on compromised sites gets the visitor to paste a command that pulls a ZIP into C:\ProgramData and silently starts a batch file.
  • After enumerating domain trusts, domain admins and AD users, the chain plants a Python implant that proxies arbitrary TCP over an encrypted WebSocket to attacker infrastructure.
  • Microsoft says it did not observe the hands-on-keyboard phase in the chain it analyzed, and describes escalation and ransomware as what usually follows this access.

Why it matters

  • What's now possible capability One pasted line converts a user workstation into a routable entry point for the attacker, so internal services become reachable without any further malware being dropped on them.
  • What it limits constraint Awareness copy that tells staff never to paste into the Run dialog no longer covers the instruction they will actually receive, and process-parentage rules written against that dialog stop matching.
  • Who's exposed exposure The recon output means the attacker leaves with a map of trusts, privileged group membership and user description fields, so scoping cannot stop at reimaging the host that ran the script.
  • Who has to decide decision Containment has to remove the Run key and the scheduled task in the same action, because clearing one buys under an hour, and the host that looks clean afterward is still compromised.

The Run dialog constrained the attacker as much as the victim: one line, pasted blind, no scrollback. That ceiling is why the usual ClickFix outcome has been a single infostealer [6]. Windows Terminal and PowerShell remove it, and Microsoft Threat Intelligence describes that as the point of the change, since complex multi-line scripts execute successfully more often when the window can take them [4].

Nothing in the chain exploits a software flaw. The user pastes the command, and that paste is the execution primitive [17]. Everything after it is built to look ordinary. The ZIP extracts to C:\ProgramData and a batch file starts LockScreenContentServer.exe, a signed legitimate binary, which loads the co-located malicious dui70.dll on its own [7][8]. Signature checking passes it. The anomaly is the directory it runs from. The second-stage fetches are PNG downloads from attacker domains, with executables and DLL fragments carried in pixel data and reassembled on disk [1], so content inspection keyed to executable payloads sees images.

Persistence is doubled: an HKCU Run key plus a scheduled task that re-executes the loader every 60 minutes [11]. At that interval the loader fires 24 times a day and 168 times a week [16]. A responder who kills the process and clears one of the two persistence points has an hour, at most, before the host comes back.

The reconnaissance is what turns this from a malware problem into an access problem. The sideloaded stage enumerates domain trusts, domain admin group membership, Active Directory computers and users, harvests AD user description fields, and pings selected servers, collecting system information in both English and Spanish locales [9]. A persistent PowerShell loop then watches a text file for further commands [13]. The chain ends with a Python reverse-tunnel implant that carries arbitrary TCP traffic back to attacker infrastructure over an encrypted WebSocket [5], a network-level proxy that operates inside the domain and gives the attacker a standing route back in.

Microsoft is careful about the boundary of what it saw. It states it did not observe the downstream hands-on-keyboard phase in the analyzed chain, and its description of privilege escalation, control tampering, exfiltration and ransomware is what typically follows this level of access rather than activity in this intrusion [10]. Its guidance is to treat affected devices as potential network pivot points and hunt for lateral movement and credential exposure [12]. The post carries indicators of compromise, detection details and hunting guidance [14]. It leaves out an observation window, a count of affected organizations, and a named actor [15].

What to watch

  • Whether Microsoft attributes the reverse-tunnel implant to a named actor or an access-broker cluster in follow-up reporting.
  • Any confirmed hands-on-keyboard case downstream of a TerminalFix tunnel, which Microsoft has not yet observed.
  • Whether the lure keeps its Cloudflare Turnstile branding once user training and web filters start matching on it.

Clarity's read

What the record supports and how the coverage leans. The claims behind it follow.

Reality

Evidence65
Adoption
Not scored
Hype gap+20
Incentives30
Confidence65

Perspective Coverage

4 publishers
Builder
Builder 20%
Operator
Operator 75%
Investor
Investor 5%
Why these scores

Claim ledger

Ranked by verification strength, evidence, and original report placement.

  1. [1]

    The sideloaded DLL runs PowerShell that downloads PNG images from attacker domains, extracts executables and DLL fragments hidden within pixel data, and reassembles them on disk.

    Reported SupportedView cited source
  2. [2]

    Microsoft Threat Intelligence has observed a TerminalFix campaign, a variant of ClickFix, targeting organizations across multiple industries.

    Reported SupportedView cited source
  3. [3]

    The campaign uses compromised websites that display a fake Cloudflare Turnstile CAPTCHA verification overlay instructing the user to copy and paste a malicious PowerShell 'verification' command.

    Reported SupportedView cited source
  4. [4]

    Traditional ClickFix campaigns direct victims to the Windows Run dialog; TerminalFix directs users to Windows Terminal or PowerShell instead, increasing the likelihood that complex, multi-line scripts execute successfully.

    Reported Supported
  5. [5]

    The chain deploys a Python-based reverse-tunnel C2 implant that tunnels arbitrary TCP traffic back through an encrypted WebSocket channel to attacker infrastructure, giving persistent network-level proxy access through the compromised host.

    Reported SupportedView cited source
  6. [6]

    Unlike earlier ClickFix variants that typically deliver a single infostealer, this TerminalFix campaign deploys a multi-stage chain combining DLL sideloading, steganographic payload extraction, extensive Active Directory reconnaissance, and a custom reverse-tunnel implant.

    Reported SupportedView cited source
  7. [7]

    The pasted PowerShell downloads a ZIP archive from attacker infrastructure containing the legitimate signed binary LockScreenContentServer.exe and a malicious DLL, dui70.dll, extracts it to C:\ProgramData, and silently launches a batch file.

    Reported SupportedView cited source
  8. [8]

    The batch file executes LockScreenContentServer.exe, a signed legitimate binary, which automatically loads the co-located malicious dui70.dll.

    Reported SupportedView cited source
  9. [9]

    Reconnaissance includes domain trust enumeration, domain admin group membership discovery, Active Directory computer and user enumeration, AD user description harvesting, targeted server ping sweeps, and system information collection in both English and Spanish locales.

    Reported SupportedView cited source
  10. [10]

    Microsoft states it did not observe the downstream actions it describes (privilege escalation, disabling security controls, exfiltration, ransomware deployment) in the analyzed chain; those are what typically follows in the hands-on-keyboard phase.

    Reported SupportedView cited source
  11. [11]

    The malware establishes dual persistence through HKCU Run registry keys and scheduled tasks that re-execute LockScreenContentServer.exe every 60 minutes.

    Reported SupportedView cited source
  12. [12]

    Microsoft advises organizations to treat affected devices as potential network pivot points and to investigate for lateral movement and credential exposure.

    Reported SupportedView cited source
  13. [13]

    A persistent PowerShell file-watch loop monitors a text file for commands to execute.

    Reported Supported
  14. [14]

    Microsoft's post includes indicators of compromise, detection details, and hunting guidance for defenders.

    Reported SupportedView cited source
  15. [15]

    Microsoft's published analysis gives no observation window or first-seen date, no count of affected organizations, and no named threat actor.

    Derived Supported
  16. [16]

    A scheduled task firing every 60 minutes re-executes the loader 24 times per day and 168 times per week.

    Derived Supported
  17. [17]

    The chain names no exploited software vulnerability; initial execution comes from the user pasting the attacker-supplied command.

    Derived Supported

Sources

4 independent publishers whose own reporting we read for this story.

  1. bleepingcomputer.com

    1 article · August 31, 2026

    Microsoft warns of TerminalFix attacks deploying reverse tunnels
  2. malwarebytes.com

    1 article · September 1, 2026

    TerminalFix looks like ClickFix, but delivers a very different payload
  3. microsoft.com

    1 article · August 28, 2026

    TerminalFix campaign deploys a reverse tunnel through multistage intrusion
  4. thehackernews.com

    2 articles · August 31, 2026

    TerminalFix Uses Fake Cloudflare CAPTCHAs to Deploy Reverse-Tunnel Backdoor

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