# CVE-2020-16009: Inappropriate implementation in V8

Source: https://junglewise.ai/threats/cve-2020-16009-google-chromium-v8-type-confusion-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2020-12-02. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2020-16009 · Severity: critical · CVSS 3.1 · Exploited in the wild · Published 2020-12-02

A type confusion vulnerability in the Google Chromium V8 engine allows a remote attacker to potentially execute arbitrary code or cause heap corruption via a crafted HTML page. The flaw was exploited in the wild prior to being patched and affects multiple Chromium-based browsers.

Technologies: [Google Chromium V8](https://junglewise.ai/threats/technologies/chromium-v8), [CefSharp.Common (NuGet)](https://junglewise.ai/threats/technologies/cefsharp-common), [CefSharp.WinForms (NuGet)](https://junglewise.ai/threats/technologies/cefsharp-winforms), [CefSharp.Wpf (NuGet)](https://junglewise.ai/threats/technologies/cefsharp-wpf), [CefSharp.Wpf.HwndHost (NuGet)](https://junglewise.ai/threats/technologies/cefsharp-wpf-hwndhost). Vendors: [Google](https://junglewise.ai/threats/vendors/google), [NuGet](https://junglewise.ai/threats/vendors/nuget).

## Quick answers

**Is CVE-2020-16009 exploited in the wild?** Yes. CVE-2020-16009 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2020-16009?** Critical severity, with a CVSS score of 3.1, published 2 December 2020.

**Which products and versions are affected?** CefSharp.Common (NuGet) ECOSYSTEM:introduced=0,fixed=86.0.241; CefSharp.WinForms (NuGet) ECOSYSTEM:introduced=0,fixed=86.0.241; CefSharp.Wpf (NuGet) ECOSYSTEM:introduced=0,fixed=86.0.241; CefSharp.Wpf.HwndHost (NuGet) ECOSYSTEM:introduced=0,fixed=86.0.241.

**Is there a fix for CVE-2020-16009?** Yes. CefSharp.Common (NuGet): upgrade to 86.0.241 or later; CefSharp.WinForms (NuGet): upgrade to 86.0.241 or later; CefSharp.Wpf (NuGet): upgrade to 86.0.241 or later; CefSharp.Wpf.HwndHost (NuGet): upgrade to 86.0.241 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2020-16009 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2020-16009?** Check whether you run Google Chromium V8, CefSharp.Common (NuGet), CefSharp.WinForms (NuGet) or one of the others listed 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

- CefSharp.Common (NuGet): upgrade to 86.0.241 or later

  ```sh
  dotnet add package CefSharp.Common --version 86.0.241
  ```

- CefSharp.WinForms (NuGet): upgrade to 86.0.241 or later

  ```sh
  dotnet add package CefSharp.WinForms --version 86.0.241
  ```

- CefSharp.Wpf (NuGet): upgrade to 86.0.241 or later

  ```sh
  dotnet add package CefSharp.Wpf --version 86.0.241
  ```

- CefSharp.Wpf.HwndHost (NuGet): upgrade to 86.0.241 or later

  ```sh
  dotnet add package CefSharp.Wpf.HwndHost --version 86.0.241
  ```


## Affected products

- Google Chrome prior to 86.0.4240.183
- Google V8 Engine
- Microsoft Edge
- Opera Opera

## Identifiers

- CVE-2020-16009
- GHSA-m7mf-48hp-5qmr

## Timeline

- 2020-11-02: patched: Stable channel update for desktop released (86.0.4240.183)
- 2021-11-03: disclosed: Published in NVD and added to CISA KEV catalog
- 2021-11-03: kev added

## Related threats

- [Google Chromium V8 out-of-bounds write in JavaScript engine](https://junglewise.ai/threats/cve-2026-87491-google-chromium-v8-out-of-bounds-write-in-javascript-engine)
- [Google Chromium V8 type confusion vulnerability](https://junglewise.ai/threats/cve-2026-85046-google-chromium-v8-type-confusion-vulnerability)
- [CefSharp.Common path traversal in FolderSchemeHandlerFactory](https://junglewise.ai/threats/cve-2026-48796-cefsharp-common-path-traversal-in-folderschemehandlerfactory)
- [Google Chrome V8 out of bounds read and write](https://junglewise.ai/threats/cve-2026-11645-google-chrome-v8-out-of-bounds-read-and-write)
- [Google Chromium V8 memory corruption in JavaScript engine](https://junglewise.ai/threats/cve-2026-3910-google-chromium-v8-memory-corruption-in-javascript-engine)