# CVE-2026-16367: Mozilla Firefox sandbox escape in Disability Access APIs

Source: https://junglewise.ai/threats/cve-2026-16367-mozilla-firefox-sandbox-escape-in-disability-access-apis  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-21. Updated: 2026-07-21  
License: CC BY 4.0 with a link back

CVE-2026-16367 · Severity: info · CVSS 8.8 · Published 2026-07-21

A security vulnerability has been identified in the Mozilla Firefox web browser's Disability Access APIs. This flaw could allow a malicious website to bypass the browser's security 'sandbox,' which is designed to keep web content isolated from the rest of the computer. If successfully exploited, an attacker could potentially gain unauthorized access to the underlying operating system, leading to data theft or the installation of malicious software.

Technologies: [Mozilla Firefox](https://junglewise.ai/threats/technologies/firefox). Vendors: [Mozilla](https://junglewise.ai/threats/vendors/mozilla).

## Quick answers

**Is CVE-2026-16367 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-16367 being exploited in the wild.

**How severe is CVE-2026-16367?** Informational severity, with a CVSS score of 8.8, published 21 July 2026.

**Which products and versions are affected?** Mozilla Firefox < 153.

**Is there a fix for CVE-2026-16367?** A patch was published on 2026-07-21: Fixed in Firefox 153 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-16367 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-16367?** Check whether you run Mozilla Firefox 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 vulnerability exists in the Disability Access APIs component of Mozilla Firefox due to an invalid pointer. This flaw allows for a sandbox escape, enabling an attacker who can execute code within the content process (typically via a malicious website) to break out of the restricted environment and execute arbitrary code with the privileges of the user running the browser. The vulnerability is triggered by improper memory handling within the accessibility framework. Mozilla has addressed this issue in Firefox 153 by improving pointer validation and memory safety within the affected component.

## Affected products

- Mozilla Firefox < 153

## Timeline

- 2026-07-21: disclosed
- 2026-07-21: patched: Fixed in Firefox 153

## References

- [https://bugzilla.mozilla.org/show_bug.cgi?id=2050627](https://bugzilla.mozilla.org/show_bug.cgi?id=2050627)
- [https://www.mozilla.org/security/advisories/mfsa2026-68/](https://www.mozilla.org/security/advisories/mfsa2026-68/)

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