Affected: Homebrew: glances

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.2, the Glances REST API web server ships with a default CORS configuration that sets `allow_origins=["*"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette's `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance. Version 4.5.2 fixes the issue.

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.2, the Glances REST API web server ships with a default CORS configuration that sets `allow_origins=["*"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette's `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance. Version 4.5.2 fixes the issue.

Affected: PyPI: Glances

## Summary

The Glances REST API web server ships with a default CORS configuration that sets `allow_origins=["*"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette's `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance.

## Details

The CORS configuration is set up in `glances/outputs/glances_restful_api.py` lines 290-299:

```python # glances/outputs/glances_restful_api.py:290-299 # FastAPI Enable CORS # https://fastapi.tiangolo.com/tutorial/cors/ self._app.add_middleware( CORSMiddleware, # Related to https://github.com/nicolargo/glances/issues/2812 allow_origins=config.get_list_value('outputs', 'cors_origins', default=["*"]), allow_credentials=config.get_bool_value('outputs', 'cors_credentials', default=True), allow_methods=config.get_list_value('outputs', 'cors_methods', default=["*"]), allow_headers=config.get_list_value('outputs', 'cors_headers', default=["*"]), ) ```

The defaults are loaded from the config file, but when no config is provided (which is the common case for most deployment…

glances-common-4.5.2-1.1 on GA media

Affected: PyPI: glances

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.2, the Glances REST API web server ships with a default CORS configuration that sets `allow_origins=["*"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette's `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance. Version 4.5.2 fixes the issue.

Affected: Ubuntu:Pro:16.04:LTS: glances, Ubuntu:Pro:18.04:LTS: glances, Ubuntu:Pro:20.04:LTS: glances, Ubuntu:22.04:LTS: glances, Ubuntu:24.04:LTS: glances, Ubuntu:25.10: glances, Ubuntu:26.04:LTS: glances

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.2, the Glances REST API web server ships with a default CORS configuration that sets `allow_origins=["*"]` combined with `allow_credentials=True`. When both of these options are enabled together, Starlette's `CORSMiddleware` reflects the requesting `Origin` header value in the `Access-Control-Allow-Origin` response header instead of returning the literal `*` wildcard. This effectively grants any website the ability to make credentialed cross-origin API requests to the Glances server, enabling cross-site data theft of system monitoring information, configuration secrets, and command line arguments from any user who has an active browser session with a Glances instance. Version 4.5.2 fixes the issue.