CVE-2021-39184

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:

delete require('electron').nativeImage.createThumbnailFromPath

For more information

If you have any questions or comments about this advisory, email us at [email protected].

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.

The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.

CVE-2021-39184 has a CVSS score of 6.8 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (11.5.0, 12.1.0, 13.3.0); upgrading removes the vulnerable code path.

Kodem intelligence

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

1. What is CVE-2021-39184? CVE-2021-39184 is a medium-severity missing authorization vulnerability in electron (npm), affecting versions < 11.5.0. It is fixed in 11.5.0, 12.1.0, 13.3.0. The application does not perform an authorization check before performing a sensitive operation.
2. How severe is CVE-2021-39184? CVE-2021-39184 has a CVSS score of 6.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of electron are affected by CVE-2021-39184? electron (npm) versions < 11.5.0 is affected.
4. Is there a fix for CVE-2021-39184? Yes. CVE-2021-39184 is fixed in 11.5.0, 12.1.0, 13.3.0. Upgrade to this version or later.
5. Is CVE-2021-39184 exploitable, and should I be worried? Whether CVE-2021-39184 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2021-39184 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2021-39184?
   • Upgrade electron to 11.5.0 or later
   • Upgrade electron to 12.1.0 or later
   • Upgrade electron to 13.3.0 or later