# CVE-2020-0878: Microsoft Edge and Internet Explorer Memory Corruption Vulnerability

Source: https://junglewise.ai/threats/cve-2020-0878-microsoft-edge-and-internet-explorer-memory-corruption  
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-2020-0878 · Severity: critical · CVSS 7.5 · Exploited in the wild · Published 2021-11-03

A memory corruption vulnerability in Microsoft Edge and Internet Explorer allows remote code execution when a user visits a specially crafted website. An attacker could execute arbitrary code in the context of the current user, potentially gaining full administrative rights if the user is logged in with such privileges.

Technologies: [Microsoft Edge](https://junglewise.ai/threats/technologies/edge), [Microsoft Internet Explorer](https://junglewise.ai/threats/technologies/internet-explorer). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2020-0878 exploited in the wild?** Yes. CVE-2020-0878 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2020-0878?** Critical severity, with a CVSS score of 7.5, published 3 November 2021.

**Which products and versions are affected?** Microsoft Edge; Microsoft Internet Explorer.

**Is there a fix for CVE-2020-0878?** 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-2020-0878 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2020-0878?** Check whether you run Microsoft Edge or Microsoft Internet Explorer. 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 Edge
- Microsoft Internet Explorer

## Timeline

- 2021-11-03: disclosed
- 2021-11-03: kev added: Added to CISA Known Exploited Vulnerabilities Catalog.
- 2021-11-03: exploited

## Related threats

- [Microsoft Edge out-of-bounds read information disclosure](https://junglewise.ai/threats/cve-2026-122518-out-of-bounds-read-in-microsoft-edge-chromium-based-allows-an)
- [Microsoft Edge privilege escalation via incorrect authorization](https://junglewise.ai/threats/cve-2026-69446-incorrect-authorization-in-microsoft-edge-chromium-based-allows)
- [Microsoft Edge use-after-free privilege elevation](https://junglewise.ai/threats/cve-2026-96203-use-after-free-in-microsoft-edge-chromium-based-allows-an)
- [Microsoft Edge heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-96199-heap-based-buffer-overflow-in-microsoft-edge-chromium-based)
- [Microsoft Edge heap-based buffer overflow](https://junglewise.ai/threats/cve-2026-96198-heap-based-buffer-overflow-in-microsoft-edge-chromium-based)