Electron subject to Exfiltration of hashed SMB credentials on Windows via file:// redirect

Summary

The Electron framework enables writing cross-platform desktop applications using JavaScript, HTML and CSS. In versions prior to 21.0.0-beta.1, 20.0.1, 19.0.11, and 18.3.7, Electron is vulnerable to Exposure of Sensitive Information. When following a redirect, Electron delays a check for redirecting to file:// URLs from other schemes. The contents of the file is not available to the renderer following the redirect, but if the redirect target is a SMB URL such as `file://some.website.com/`, then in some cases, Windows will connect to that server and attempt NTLM authentication, which can include sending hashed credentials.This issue has been patched in versions: 21.0.0-beta.1, 20.0.1, 19.0.11, and 18.3.7. Users are recommended to upgrade to the latest stable version of Electron. If upgrading isn't possible, this issue can be addressed without upgrading by preventing redirects to file:// URLs in the `WebContents.on('will-redirect')` event, for all WebContents as a workaround.

Timeline

1. Nov 8, 2022, 12:00 AM UTCCVE published
2. Apr 23, 2025, 3:49 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: partial

3. Apr 23, 2025, 4:40 PM UTCRecord last updated

Affected versions

• electron electron

  From v21.0.0-nightly.20220526 · fixed in 21.0.0-beta.1; From 20.0.0-beta.1 · fixed in 20.0.1; From 19.0.0-beta.1 · fixed in 19.0.11; fixed in 18.3.7

• electronnpm

  fixed in 18.3.7

• electronnpm

  From 20.0.0-beta.1 · fixed in 20.0.1

• electronnpm

  From 19.0.0-beta.1 · fixed in 19.0.11

References 1