fix(security): enforce case-insensitive sensitive path blocklist and vscode hitl

[luisfelipe-alt]

Summary

This PR implements a 100% robust, production-grade security fix for the case-insensitivity bypass and prompt injection vulnerability in Gemini CLI. It enforces a strict, case-insensitive blocklist for sensitive directories/files (.git, .env, node_modules) and ensures that any modifications to .vscode/ configuration files always require explicit user confirmation (Human-in-the-Loop), even in automated modes like autoEdit or YOLO.

Details

• Case-Insensitive Segment Blocklist in WorkspaceContext: Updated isPathWithinWorkspace in packages/core/src/utils/workspaceContext.ts to split resolved paths into segments and check them case-insensitively against ['.git', '.env', 'node_modules'].
• Case-Insensitive Segment Blocklist in AllowedPathChecker: Updated AllowedPathChecker in packages/core/src/safety/built-in.ts to enforce the same case-insensitive segment blocklist check, returning SafetyCheckDecision.DENY if matched.
• Mandatory HITL Confirmation for .vscode/ Configuration Files: Updated AllowedPathChecker to detect if a path is inside .vscode/ (case-insensitively) and return SafetyCheckDecision.ASK_USER, which downgrades the policy engine's decision to ASK_USER (requiring explicit user confirmation) even in automated modes like autoEdit or YOLO.
• Comprehensive Regression Tests: Added unit tests to packages/core/src/utils/workspaceContext.test.ts and packages/core/src/safety/built-in.test.ts to verify the fix.

Related Issues

How to Validate

1. Run the specific unit tests to verify that the security fixes and regression tests are working perfectly:

   npx vitest run packages/core/src/utils/workspaceContext.test.ts packages/core/src/safety/built-in.test.ts

2. Verify that all 56 tests pass successfully.
3. Run the TypeScript type checker to ensure everything compiles perfectly:

   npm run typecheck

Pre-Merge Checklist

• Updated relevant documentation and README (if needed)
• Added/updated tests (if needed)
• Noted breaking changes (if any)
• Validated on required platforms/methods:
  • Linux
    • npm run

[github-actions]

📊 PR Size: size/M

• Lines changed: 203
• Additions: +192
• Deletions: -11
• Files changed: 4

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces critical security enhancements to the Gemini CLI by hardening path validation logic. By enforcing case-insensitive checks on sensitive directory segments and requiring explicit user approval for modifications to IDE configuration files, the changes mitigate potential vulnerabilities related to path traversal and unauthorized configuration tampering in automated execution environments.

Highlights

• Case-Insensitive Security Blocklist: Implemented a robust, case-insensitive check for sensitive directories and files ('.git', '.env', 'node_modules') in both the workspace context and the path checker to prevent security bypasses.
• Mandatory Human-in-the-Loop (HITL) for .vscode: Enforced a requirement for explicit user confirmation when modifying files within '.vscode/', ensuring that automated modes cannot silently alter configuration settings.
• Regression Testing: Added comprehensive unit tests to verify the new security constraints and ensure that sensitive paths are correctly blocked regardless of casing.

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[gemini-code-assist]

Code Review

This pull request implements case-insensitive blocklist checks for sensitive paths (like .git, .env, and node_modules) and requires user confirmation (ASK_USER) for .vscode configuration files. The review highlights critical security issues, including a sandbox bypass where .vscode paths outside the workspace incorrectly trigger ASK_USER instead of DENY, and a Windows trailing character bypass (e.g., .git or .vscode.). The feedback suggests validating workspace allowance before checking blocked segments, handling trailing spaces/dots, using a unified path resolution function (resolveToRealPath), and adding regression tests to verify these edge cases.

[luisfelipe-alt]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces case-insensitive blocklist checks for sensitive paths (such as .git, .env, and node_modules) and requires explicit user confirmation for .vscode configuration files. It also adds comprehensive regression tests to verify these security controls. The review feedback highlights potential bypasses on Windows via NTFS Alternate Data Streams (e.g., .vscode::$DATA) and suggests stripping stream identifiers during segment cleaning, as well as using a unified path resolution function like resolveToRealPath to ensure consistent validation across components.

[luisfelipe-alt]

/gemini review

[gemini-code-assist]

Code Review

This pull request implements case-insensitive blocklist checks for sensitive paths (such as .git, .env, and node_modules) and requires explicit user confirmation (ASK_USER) for modifying .vscode configuration files within the workspace. The feedback suggests refactoring the path validation logic to use asynchronous file system operations instead of synchronous ones to avoid blocking the event loop, and ensuring consistent path resolution.

[luisfelipe-alt]

/gemini review

[gemini-code-assist]

Code Review

This pull request implements a case-insensitive blocklist for sensitive paths (such as ".git", ".env", and "node_modules") and adds special handling for ".vscode" configuration files to prevent security bypasses, including Windows trailing characters and NTFS Alternate Data Streams. It also refactors safelyResolvePath to use asynchronous file system operations and adds comprehensive regression tests. There are no review comments, and I have no feedback to provide.