# CVE-2026-72970: Microsoft Edge heap-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-72970-microsoft-edge-heap-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-14. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-72970 · Severity: high · CVSS 8.3 · Published 2026-08-14

Microsoft Edge is a web browser used by millions to access websites and web applications. A heap memory overflow vulnerability allows attackers to execute arbitrary code on a user's computer by tricking them into visiting a malicious website, potentially leading to data theft, account compromise, or system takeover.

Technologies: [Microsoft Edge](https://junglewise.ai/threats/technologies/edge), [Microsoft Edge Chromium](https://junglewise.ai/threats/technologies/edge-chromium). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-72970 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-72970 being exploited in the wild.

**How severe is CVE-2026-72970?** High severity, with a CVSS score of 8.3, published 14 August 2026.

**Which products and versions are affected?** Microsoft Edge.

**Is there a fix for CVE-2026-72970?** 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-2026-72970 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-72970?** Check whether you run Microsoft Edge or Microsoft Edge Chromium. 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.

## Technical details

A heap-based buffer overflow exists in Microsoft Edge (Chromium-based browser). The vulnerability can be exploited over the network without authentication; an attacker crafts a malicious webpage that, when visited by a user, triggers the overflow condition in memory. This allows arbitrary code execution within the browser process with user privileges. Microsoft has released a security update to address this issue.

## Affected products

- Microsoft Edge

## Timeline

- 2026-08-14: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-72970](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-72970)

## Related threats

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- [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)