Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. A vulnerability in versions prior to 11.5.0, 12.1.0, and 13.3.0 allows a sandboxed renderer to request a "thumbnail" image of an arbitrary file on the user's system. The thumbnail can potentially include significant parts of the original file, including textual data in many cases. Versions 15.0.0-alpha.10, 14.0.0, 13.3.0, 12.1.0, and 11.5.0 all contain a fix for the vulnerability. Two workarounds aside from upgrading are available. One may make the vulnerability significantly more difficult for an attacker to exploit by enabling `contextIsolation` in one's app. One may also disable the functionality of the `createThumbnailFromPath` API if one does not need it.

Affected: npm: electron

### Impact This vulnerability allows a sandboxed renderer to request a "thumbnail" image of an arbitrary file on the user's system. The thumbnail can potentially include significant parts of the original file, including textual data in many cases.

All current stable versions of Electron are affected.

### Patches This was fixed with #30728, and the following Electron versions contain the fix:

- 15.0.0-alpha.10 - 14.0.0 - 13.3.0 - 12.1.0 - 11.5.0

### Workarounds If your app enables `contextIsolation`, this vulnerability is significantly more difficult for an attacker to exploit.

Further, if your app does not depend on the `createThumbnailFromPath` API, then you can simply disable the functionality. In the main process, before the 'ready' event: ```js delete require('electron').nativeImage.createThumbnailFromPath ```

### For more information If you have any questions or comments about this advisory, email us at [security@electronjs.org](mailto:security@electronjs.org).