fix(tools): restrict CORS origin in Dev UI server#5259
Merged
MichaelDoyle merged 2 commits intogenkit-ai:mainfrom May 7, 2026
Merged
fix(tools): restrict CORS origin in Dev UI server#5259MichaelDoyle merged 2 commits intogenkit-ai:mainfrom
MichaelDoyle merged 2 commits intogenkit-ai:mainfrom
Conversation
|
Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA). View this failed invocation of the CLA check for more information. For the most up to date status, view the checks section at the bottom of the pull request. |
![gemini-code-assist[bot]](https://avatars.githubusercontent.com/in/956858?s=60&v=4){kind=small}
Contributor
There was a problem hiding this comment.
Code Review
This pull request introduces security enhancements by filtering sensitive environment variables from the Dev UI and restricting CORS origins. Feedback suggests expanding the sensitive pattern list to include 'AUTH' and 'SALT' and improving the CORS origin configuration to support '127.0.0.1' and handle potential port assignment issues.
MichaelDoyle
reviewed
May 7, 2026
The Dev UI server uses `Access-Control-Allow-Origin: *`, allowing any website to make cross-origin requests and read responses. This enables credential theft via CSRF when combined with the getGenkitEnvironment endpoint. Restrict CORS to localhost origins using the same regex pattern as the telemetry server.
q1uf3ng
force-pushed
the
fix/devui-cors-env-leak
branch
from
e00a681 to
c95d125
Compare
q1uf3ng
changed the title
Removed comment about localhost origins in CORS configuration.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
The Dev UI server has two security issues:
CORS wildcard (
server.ts):Access-Control-Allow-Origin: *is hardcoded, allowing any website to make cross-origin requests and read responses.Environment variable disclosure (
router.ts):getGenkitEnvironmentreturns every environment variable without filtering, includingGOOGLE_API_KEY,GEMINI_API_KEY, and other secrets.Combined, any website a developer visits while running
genkit startcan silently read all their API keys via cross-origin fetch.Fix
http://localhost:{port}(the Dev UI itself)Reproduction