Windows Defender flags unsigned codex-computer-use.exe command line as Trojan:Win32/ClickFix.DE!MTB

What version of the Codex App are you using?

Codex Desktop on Windows.

Verified local package path:

C:\Program Files\WindowsApps\OpenAI.Codex_26.623.19656.0_x64__2p2nqsd0c76g0\app\resources\codex.exe

The main codex.exe file did not expose embedded ProductVersion / FileVersion metadata through Windows file version info.

What subscription do you have?

ChatGPT Pro

What platform is your computer?

Windows.

What issue are you seeing?

Microsoft Defender flagged normal Codex Desktop Computer Use activity as a severe ClickFix trojan:

Threat: Trojan:Win32/ClickFix.DE!MTB
Threat ID: 2147932647
Category: Trojan
Severity: Severe
Detection time: 2026-07-07 10:10 AM America/New_York
Defender intelligence: AV 1.453.463.0, AS 1.453.463.0, NIS 1.453.463.0
Engine: AM 1.1.26050.11, NIS 1.1.26050.11

The affected item was a command line for the Windows Computer Use helper:

C:\Users\<user>\AppData\Local\OpenAI\Codex\runtimes\cua_node\1b23c930bdf84ed6\bin\node_modules\@oai\sky\bin\windows\codex-computer-use.exe turn-ended ...

The command line contained a normal Codex Desktop agent-turn-complete / turn-ended payload with thread metadata and recent user/assistant prompt text. This appears to be a Defender heuristic hit on the Computer Use helper invocation and/or its long prompt-bearing command line, not a user-downloaded executable.

Local Defender readback after the alert:

ThreatID: 2147932647
ThreatName: Trojan:Win32/ClickFix.DE!MTB
DidThreatExecute: False
IsActive: False
Action: Remove
Action Status: No additional actions required

Important: clicking "Allow" in Windows Security persisted a threat-specific default action:

ThreatIDDefaultAction_Ids: {2147932647}
ThreatIDDefaultAction_Actions: {6}

That means the UX can lead users to allow the whole threat ID rather than making a narrow trust decision about a specific Codex helper binary.

The helper binary was present on disk, but it was not signed and did not expose embedded ProductVersion / FileVersion metadata:

Path: C:\Users\<user>\AppData\Local\OpenAI\Codex\runtimes\cua_node\1b23c930bdf84ed6\bin\node_modules\@oai\sky\bin\windows\codex-computer-use.exe
Authenticode status: NotSigned
Embedded ProductVersion: <empty>
Embedded FileVersion: <empty>
@oai/sky package version: 0.4.19
File size: 1,691,648 bytes
Created: 2026-06-22 09:29:05 local time
LastWriteTime: 2026-06-11 19:00:17 local time
SHA256: F2B2F56FCD1699B0FA32DEC3214A56A1D36B937A2ECF58CC822AB4A904551E03

What steps can reproduce the bug?

I do not have a deterministic minimal repro yet. The observed flow was:

1. Use Codex Desktop on Windows.
2. Use or have enabled Computer Use.
3. A Codex thread completed a turn.
4. Defender flagged codex-computer-use.exe turn-ended ... as Trojan:Win32/ClickFix.DE!MTB.
5. Windows Security offered an "Allow" path that persisted a Defender threat action for threat ID 2147932647.

What is the expected behavior?

Normal Codex Desktop Computer Use helper activity should not trigger Microsoft Defender as a severe ClickFix trojan.

Please consider:

• code-signing codex-computer-use.exe and any other bundled Windows helper binaries;
• submitting the signed helper and current hash to Microsoft for Defender reputation / false-positive review;
• avoiding command-line shapes where large prompt/thread payloads are passed directly to a helper in a way that resembles ClickFix or command-from-attacker behavior;
• making the product guidance clearer when Defender fires, because "Allow" can create a broad persistent threat allow entry instead of a narrow Codex helper allow.

I do not want to disable Computer Use. I also do not want to use broad Defender exclusions for the Codex runtime tree. A durable product-side fix seems needed.

Related issues

These appear adjacent but not exact duplicates:

• #15423: On Windows, some tool-generated PowerShell commands can be blocked by Defender as Trojan:Win32/ClickFix.SA!A
• #26218: Windows Defender Severe alert from Codex-generated pwsh reflection command
• #20315: browser-use (browser-client.mjs) marked as trojan by Windows Defender
• #31251: macOS detects Codex Computer Use.app as malware and deletes it!

This issue differs from the macOS signing/Gatekeeper reports because the affected item is the Windows Computer Use helper executable (codex-computer-use.exe), the detection is Microsoft Defender Trojan:Win32/ClickFix.DE!MTB, and Windows Security persisted a threat-ID allow entry after the user clicked "Allow." The shared theme is that Computer Use helper packaging/signing/reputation needs attention across platforms.