Unknown actor ExtHostShellExec

[laben]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Since today, all agent terminal actions (Auto mode/Sonnet-4) fail with the following message:

“Unknown actor ExtHostShellExec”

Cursor no longer seems to be able to run terminal actions. It can edit files still but prompts me to run all terminal actions manually. I have zsh installed but up to yesterday there were no issues. I updated to Version: 1.6.6 this morning.

Steps to Reproduce

Try to run any terminal command (ls , npm.. whatever) using Agent mode.

Screenshots / Screen Recordings

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Version: 1.6.6
VSCode Version: 1.99.3
Commit: 9455eaa4c87f2bad91eda3f2bc9b42b16eae1080
Date: 2025-09-11T01:16:54.096Z (7 hrs ago)
Electron: 34.5.8
Chromium: 132.0.6834.210
Node.js: 20.19.1
V8: 13.2.152.41-electron.0
OS: Darwin arm64 24.6.0

For AI issues: which model did you use?

Auto/Sonnet-4

For AI issues: add Request ID with privacy disabled

8b0ea1f4-9cb2-4be3-b2d1-1186ecf8dabe

Does this stop you from using Cursor

NO - Cursor is not unusable, but Agent mode is severely limited.

[deanrie]

Hey, thanks for the report. Could you let me know if this also happens in a new chat? I just checked and couldn’t reproduce it. Could you also try this in another project? Also, try updating Cursor to version 1.6.10, as it might have already been fixed.

[laben]

Hi @deanrie thanks for helping out.

It happens in new chats, it happens after restarting cursor. It happens in other projects (folders).

I am not sure how to update to version 1.6.10, since I was already at the latest version according to Cursor.

I seemed to have fixed it by manually downloading and downgrading to the previous stable version (1.5.11) for ARM64:

Version: 1.5.11
VSCode Version: 1.99.3
Commit: 2f2737de9aa376933d975ae30290447c910fdf40
Date: 2025-09-05T03:48:32.332Z (6 days ago).

The agent is now again able to access the terminal. I think it has to do with a bug in version 1.6.6..

[deanrie]

Yes, most likely. In any case, the new version will be available soon. Let me know if it doesn’t fix the issue.

[condor (Condor (Tee))]

Yes fix is on the way.

"My shell path can’t access your repo path right now”

Will be a new version - 1.6.12 - in about 1.5 hours

[andrewh (Andrew Milich)]

Fixed in the latest version.