DOM Clobbering Gadget found in rollup bundled scripts that leads to XSS
Date: 2024-09
Affected: npm/rollup, npm/rollup, npm/rollup
Attack vector: xss
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2024-47068
CWE: CWE-79
CVSS: 6.4 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H)

### Summary 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](https://github.com/webpack/webpack/security/advisories/GHSA-4vvj-4cpr-p986)), which might serve as a good reference. ### Details #### Backgrounds 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/ #### Gadget found in `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/


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