Comment by roywiggins
1 day ago
The user didn't need to give it curl permission, that's the whole issue:
> Copilot also has an external URL access check that requires user approval when commands like curl, wget, or Copilot’s built-in web-fetch tool request access to external domains [1].
> This article demonstrates how attackers can craft malicious commands that go entirely undetected by the validator - executing immediately on the victim’s computer with no human-in-the-loop approval whatsoever.
I think there's different conversations happening and I don't think we're having the same conversation.
This is the claim by the article: "Vulnerabilities in the GitHub Copilot CLI expose users to the risk of arbitrary shell command execution via indirect prompt injection without any user approval"
But this is not true, the author gave explicit permission on copilot startup to trust and execute code in the folder.
Here's the exact starting screen on copilot:
│ Confirm folder trust │ │ │ │ ╭─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮ │ │ │ /Users/me/Documents │ │ │ ╰─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯ │ │ │ │ Copilot may read files in this folder. Reading untrusted files may lead Copilot to behave in unexpected ways. With your permission, Copilot may execute │ │ code or bash commands in this folder. Executing untrusted code is unsafe. │ │ │ │ Do you trust the files in this folder? │ │ │ │ 1. Yes │ │ 2. Yes, and remember this folder for future sessions │ │ 3. No (Esc) │
And `The injection is stored in a README file from the cloned repository, which is an untrusted codebase.`
"With your permission, Copilot may execute code or bash commands in this folder." could be interpreted either way I suppose, but the actual question is "do you trust the files in this folder" and not "do you trust Copilot to execute any bash commands it wants without further permissions prompts".
The risk isn't solely that there might be a prompt injection, Copilot could just discover `env sh` doesn't need a user prompt and just start using that spontaneously and bypassing user confirmation. If you haven't started Copilot in yolo mode that would be very surprising and risky.
If it usually asks for user confirmation before running bash commands then there should, ideally, not be a secret yolo mode that the agent can just start using without asking. That's obviously a bad idea!
"Actually copilot is always secretly in yolo mode, that's working as designed" seems like a pretty serious violation of expectations. Why even have any user confirmations at all?
If the user is working in a folder where copilot can discover a malicious `env sh` to run, the user should not give permission to trust the files in the folder.
I think it's a valid observation that we can bypass the coding AI's user prompting gate with the right prompt. That is a valid limitation of LLM supported agentic workflows today.
But that's not what this article claims. The article claims that there was no user approval and no user interaction beyond initial query and that the copilot is downloading + executing malware.
I'm saying this is sensationalized and not a novel technical vulnerability write up.
The author explicitly gave approval for copilot to trust "untrusted repository". Crafted a file which had instructions to do a curl command despite the warnings on copilot start up. It is not operating secretly in yolo mode.
If the claim of the article is "Copilot doesn't gate tool calls with env", I'd have a different response. But I also have to mention, you can tune approved tool calls.