Unmarshall update

[DavidAPierce]

Summary

Added an ignore list for object keys when unmarshalling JSON in recursivelyHydrateStrings.

Details

The recursivelyHydrateStrings function now sanitizes object keys by skipping proto, constructor, and prototype.
Added tests to verify this.

Related Issues

Fixes https://github.com/google-gemini/maintainers-gemini-cli/issues/1499

[gemini-cli]

Hi @DavidAPierce, thank you so much for your contribution to Gemini CLI! We really appreciate the time and effort you've put into this.

We're making some updates to our contribution process to improve how we track and review changes. Please take a moment to review our recent discussion post: Improving Our Contribution Process & Introducing New Guidelines.

Key Update: Starting January 26, 2026, the Gemini CLI project will require all pull requests to be associated with an existing issue. Any pull requests not linked to an issue by that date will be automatically closed.

Thank you for your understanding and for being a part of our community!

[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 addresses a potential security vulnerability by enhancing the recursivelyHydrateStrings function. It introduces a mechanism to filter out specific object keys during JSON unmarshalling, thereby safeguarding against prototype pollution attacks and improving the overall robustness of the application's data processing.

Highlights

• Security Enhancement: Implemented an ignore list for object keys (__proto__, constructor, prototype) during JSON unmarshalling in recursivelyHydrateStrings to prevent prototype pollution vulnerabilities.
• Test Coverage: Added new unit tests to verify that the recursivelyHydrateStrings function correctly prevents prototype pollution via __proto__, constructor, and prototype.

Changelog

• packages/cli/src/config/extensions/variables.test.ts
  • Added three new test cases to validate the prevention of prototype pollution through __proto__, constructor, and prototype keys.
• packages/cli/src/config/extensions/variables.ts
  • Defined UNMARSHALL_KEY_IGNORE_LIST to hold keys that should be ignored during JSON unmarshalling.
  • Modified recursivelyHydrateStrings to check against this ignore list before processing object keys.

Activity

• No human activity has been recorded on this pull request yet.

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[gemini-code-assist]

Code Review

This pull request introduces a crucial security fix by preventing prototype pollution in the recursivelyHydrateStrings function. The changes include adding an ignore list for specific object keys (__proto__, constructor, prototype) during JSON unmarshalling and updating the recursivelyHydrateStrings function to utilize this list. New test cases have also been added to verify the effectiveness of this fix against prototype pollution. This is a significant improvement for the security posture of the application.

[github-actions]

Size Change: +145 B (0%)

Total Size: 26 MB

ℹ️ View Unchanged

Filename	Size	Change
./bundle/gemini.js	25.5 MB	+145 B (0%)
./bundle/node_modules/@google/gemini-cli-devtools/dist/client/main.js	221 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/_client-assets.js	227 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/index.js	11.5 kB	0 B
./bundle/node_modules/@google/gemini-cli-devtools/dist/src/types.js	132 B	0 B
./bundle/sandbox-macos-permissive-open.sb	890 B	0 B
./bundle/sandbox-macos-permissive-proxied.sb	1.31 kB	0 B
./bundle/sandbox-macos-restrictive-open.sb	3.36 kB	0 B
./bundle/sandbox-macos-restrictive-proxied.sb	3.56 kB	0 B
./bundle/sandbox-macos-strict-open.sb	4.82 kB	0 B
./bundle/sandbox-macos-strict-proxied.sb	5.02 kB	0 B

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