# CVE-2026-54257: Electron heap buffer overflow in Node.js Buffer API

Source: https://junglewise.ai/threats/cve-2026-54257-electron-heap-buffer-overflow-in-node-js-buffer-api  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-23. Updated: 2026-06-23  
License: CC BY 4.0 with a link back

CVE-2026-54257 · Severity: critical · CVSS 4 · Published 2026-06-23

Electron, a widely used framework for building desktop applications like Slack and Discord, contains a flaw in how it handles data memory. This issue can cause applications to crash or behave unpredictably, potentially allowing attackers to disrupt services or gain unauthorized access to data. Users should ensure their desktop applications are updated to versions using the patched framework.

Technologies: [electron (npm)](https://junglewise.ai/threats/technologies/electron). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-54257 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-54257 being exploited in the wild.

**How severe is CVE-2026-54257?** Critical severity, with a CVSS score of 4, published 23 June 2026.

**Which products and versions are affected?** electron (npm) >= 42.3.1, < 42.3.3, SEMVER:introduced=42.3.1,fixed=42.3.3.

**Is there a fix for CVE-2026-54257?** Yes. electron (npm): upgrade to 42.3.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-54257 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-54257?** Check whether you run electron (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- electron (npm): upgrade to 42.3.3 or later

  ```sh
  npm install electron@42.3.3
  ```


## Technical details

A vulnerability exists in Electron's implementation of the Node.js Buffer API between versions 42.3.1 and 42.3.2. The root cause is incorrect byte length calculations during memory allocation, leading to classic buffer overflows or underflows (CWE-120) on the heap. An attacker can potentially exploit this over a network without authentication to cause a Denial of Service (crash) or achieve remote code execution through memory corruption. The issue is resolved in Electron version 42.3.3.

## Affected products

- Electron Electron 42.3.1 - 42.3.2

## Identifiers

- CVE-2026-54257
- GHSA-q6m5-f73j-m9mc

## Timeline

- 2026-06-03: advisory: GitHub advisory published by Electron maintainers
- 2026-06-23: disclosed: CVE published to NVD

## References

- [https://github.com/electron/electron/security/advisories/GHSA-q6m5-f73j-m9mc](https://github.com/electron/electron/security/advisories/GHSA-q6m5-f73j-m9mc)

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