# CVE-2026-58299: Microsoft Edge for Android TOCTOU race condition

Source: https://junglewise.ai/threats/cve-2026-58299-microsoft-edge-for-android-toctou-race-condition  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-03. Updated: 2026-07-03  
License: CC BY 4.0 with a link back

CVE-2026-58299 · Severity: high · CVSS 7.5 · Published 2026-07-03

Microsoft Edge for Android is a mobile web browser used to access the internet and corporate web applications. A security flaw has been identified that could allow a remote attacker to execute malicious code on a user's device if they are tricked into visiting a specifically crafted website. This could lead to the theft of sensitive data, unauthorized access to accounts, or a complete compromise of the mobile device.

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

## Quick answers

**Is CVE-2026-58299 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58299 being exploited in the wild.

**How severe is CVE-2026-58299?** High severity, with a CVSS score of 7.5, published 3 July 2026.

**Which products and versions are affected?** Microsoft Edge < 150.0.4078.48.

**Is there a fix for CVE-2026-58299?** 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-2026-58299 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-58299?** Check whether you run Microsoft Edge 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.

## Technical details

A race condition vulnerability (CWE-367) exists in Microsoft Edge (Chromium-based) for Android. The flaw is a Time-of-Check Time-of-Use (TOCTOU) issue that occurs during the processing of web content. An unauthenticated remote attacker can exploit this by enticing a user to visit a malicious webpage or interact with specially crafted content. Successful exploitation requires the attacker to win a timing race, which if successful, allows for arbitrary code execution in the context of the browser. Microsoft has addressed this in version 150.0.4078.48 and later.

## Affected products

- Microsoft Edge (Chromium-based) for Android < 150.0.4078.48

## Timeline

- 2026-07-03: advisory: Initial advisory published by Microsoft and NVD.

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58299](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58299)

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