The webpack-dev-middleware middleware does not validate the supplied URL address sufficiently before returning the local file. It is possible to access any file on the developer's machine.
A blank project can be created containing the following configuration file webpack.config.js:module.exports = { devServer: { devMiddleware: { writeToDisk: true } } };
When started, it is possible to access any local file, e.g. /etc/passwd:
$ curl localhost:8080/public/..%2f..%2f..%2f..%2f../etc/passwd
The developers using webpack-dev-server or webpack-dev-middleware are affected by the issue. When the project is started, an attacker might access any file on the developer's machine and exfiltrate the content (e.g. password, configuration files, private source code, ...).
If the development server is listening on a public IP address (or 0.0.0.0), an attacker on the local network can access the local files without any interaction from the victim (direct connection to the port).
If the server allows access from third-party domains (CORS, *_Allow-Access-Origin: _** ), an attacker can send a malicious link to the victim. When visited, the client side script can connect to the local server and exfiltrate the local files.
Recommendation
The URL should be unescaped and normalized before any further processing.
Release Notes
webpack/webpack-dev-middleware (webpack-dev-middleware)
### [`v7.1.0`](https://redirect.github.com/webpack/webpack-dev-middleware/blob/HEAD/CHANGELOG.md#710-2024-03-19)
[Compare Source](https://redirect.github.com/webpack/webpack-dev-middleware/compare/v7.0.0...v7.1.0)
##### Features
- prefer to use `fs.createReadStream` over `fs.readFileSync` to read files ([ab533de](https://redirect.github.com/webpack/webpack-dev-middleware/commit/ab533de933c6684218172b86992f35c3ca6c58a4))
##### Bug Fixes
- cleaup stream and handle errors ([#1769](https://redirect.github.com/webpack/webpack-dev-middleware/issues/1769)) ([1258fdd](https://redirect.github.com/webpack/webpack-dev-middleware/commit/1258fdd3d9c175dbacf6bc3b36d5c3c545738f13))
- **security:** do not allow to read files above ([#1771](https://redirect.github.com/webpack/webpack-dev-middleware/issues/1771)) ([e10008c](https://redirect.github.com/webpack/webpack-dev-middleware/commit/e10008c762e4d5821ed6990348dabf0d4d93a10e))
Configuration
📅 Schedule: Branch creation - "" (UTC), Automerge - At any time (no schedule defined).
🚦 Automerge: Enabled.
♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.
🔕 Ignore: Close this PR and you won't be reminded about these updates again.
[ ] If you want to rebase/retry this PR, check this box
This PR contains the following updates:
7.0.0->7.1.0GitHub Vulnerability Alerts
CVE-2024-29180
Summary
The webpack-dev-middleware middleware does not validate the supplied URL address sufficiently before returning the local file. It is possible to access any file on the developer's machine.
Details
The middleware can either work with the physical filesystem when reading the files or it can use a virtualized in-memory memfs filesystem. If writeToDisk configuration option is set to true, the physical filesystem is used: https://github.com/webpack/webpack-dev-middleware/blob/7ed24e0b9f53ad1562343f9f517f0f0ad2a70377/src/utils/setupOutputFileSystem.js#L21
The getFilenameFromUrl method is used to parse URL and build the local file path. The public path prefix is stripped from the URL, and the unsecaped path suffix is appended to the outputPath: https://github.com/webpack/webpack-dev-middleware/blob/7ed24e0b9f53ad1562343f9f517f0f0ad2a70377/src/utils/getFilenameFromUrl.js#L82 As the URL is not unescaped and normalized automatically before calling the midlleware, it is possible to use %2e and %2f sequences to perform path traversal attack.
PoC
A blank project can be created containing the following configuration file webpack.config.js:
module.exports = { devServer: { devMiddleware: { writeToDisk: true } } };When started, it is possible to access any local file, e.g. /etc/passwd:
$ curl localhost:8080/public/..%2f..%2f..%2f..%2f../etc/passwdImpact
The developers using webpack-dev-server or webpack-dev-middleware are affected by the issue. When the project is started, an attacker might access any file on the developer's machine and exfiltrate the content (e.g. password, configuration files, private source code, ...).
If the development server is listening on a public IP address (or 0.0.0.0), an attacker on the local network can access the local files without any interaction from the victim (direct connection to the port).
If the server allows access from third-party domains (CORS, *_Allow-Access-Origin: _** ), an attacker can send a malicious link to the victim. When visited, the client side script can connect to the local server and exfiltrate the local files.
Recommendation
The URL should be unescaped and normalized before any further processing.
Release Notes
webpack/webpack-dev-middleware (webpack-dev-middleware)
### [`v7.1.0`](https://redirect.github.com/webpack/webpack-dev-middleware/blob/HEAD/CHANGELOG.md#710-2024-03-19) [Compare Source](https://redirect.github.com/webpack/webpack-dev-middleware/compare/v7.0.0...v7.1.0) ##### Features - prefer to use `fs.createReadStream` over `fs.readFileSync` to read files ([ab533de](https://redirect.github.com/webpack/webpack-dev-middleware/commit/ab533de933c6684218172b86992f35c3ca6c58a4)) ##### Bug Fixes - cleaup stream and handle errors ([#1769](https://redirect.github.com/webpack/webpack-dev-middleware/issues/1769)) ([1258fdd](https://redirect.github.com/webpack/webpack-dev-middleware/commit/1258fdd3d9c175dbacf6bc3b36d5c3c545738f13)) - **security:** do not allow to read files above ([#1771](https://redirect.github.com/webpack/webpack-dev-middleware/issues/1771)) ([e10008c](https://redirect.github.com/webpack/webpack-dev-middleware/commit/e10008c762e4d5821ed6990348dabf0d4d93a10e))Configuration
📅 Schedule: Branch creation - "" (UTC), Automerge - At any time (no schedule defined).
🚦 Automerge: Enabled.
♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.
🔕 Ignore: Close this PR and you won't be reminded about these updates again.
This PR was generated by Mend Renovate. View the repository job log.