# CVE-2020-0646: Microsoft .NET Framework Remote Code Execution Vulnerability

Source: https://junglewise.ai/threats/cve-2020-0646-microsoft-net-framework-remote-code-execution-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2020-0646 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2021-11-03

A remote code execution vulnerability exists in Microsoft .NET Framework due to improper input validation, specifically involving XOML injection. An attacker can exploit this to execute arbitrary code on a target system without user interaction.

Technologies: [Microsoft .NET Framework](https://junglewise.ai/threats/technologies/net-framework). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2020-0646 exploited in the wild?** Yes. CVE-2020-0646 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2020-0646?** Critical severity, with a CVSS score of 9.8, published 3 November 2021.

**Which products and versions are affected?** Microsoft .NET Framework 3.5, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8.

**Is there a fix for CVE-2020-0646?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2020-0646 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2020-0646?** Check whether you run Microsoft .NET Framework. 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.

## Affected products

- Microsoft .NET Framework 3.5, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8

## Timeline

- 2020-02-11: disclosed: Initial release date of the vulnerability advisory by Microsoft.
- 2021-11-03: kev added: Added to CISA's Known Exploited Vulnerabilities Catalog.
- 2021-11-03: disclosed: NVD publication date.

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