PatchSiren cyber security CVE debrief
CVE-2026-16352 Mozilla CVE debrief
A critical vulnerability, CVE-2026-16352, was published on 2026-07-21T13:17:03.693Z. It involves a sandbox escape due to a use-after-free in the Disability Access APIs component. This issue was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13. The vulnerability allows attackers to bypass the sandbox, potentially leading to arbitrary code execution. Organizations should prioritize patching to mitigate this critical vulnerability.
- Vendor
- Mozilla
- Product
- Firefox
- CVSS
- CRITICAL 9.8
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-07-21
- Original CVE updated
- 2026-07-22
- Advisory published
- 2026-07-21
- Advisory updated
- 2026-07-22
Who should care
Organizations and individuals using Firefox, Firefox ESR, and Thunderbird should prioritize patching to prevent potential sandbox escapes. This vulnerability can be particularly dangerous for organizations that rely on these applications for critical tasks or handle sensitive information.
Technical summary
CVE-2026-16352 is a critical vulnerability caused by a use-after-free in the Disability Access APIs component, allowing for sandbox escapes. It was fixed in multiple versions of Firefox, Firefox ESR, and Thunderbird. The CVSS score for this vulnerability is 9.8, indicating a high severity level. This type of vulnerability can be used to bypass security mechanisms, potentially leading to arbitrary code execution.
Defensive priority
High
Recommended defensive actions
- Apply patches for Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
- Inventory checks for affected products and prioritize patching.
- Implement compensating controls, such as monitoring for suspicious activity.
- Exception tracking for any systems that cannot be patched immediately.
- Review relevant monitoring, detection, and logs for exposed assets that need extra review.
- Track exceptions, retest remediated assets, and close the item only after evidence is documented.
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
Evidence notes
The CVE record was published on 2026-07-21T13:17:03.693Z and last modified on 2026-07-22T20:16:50.213Z. The NVD entry is currently Undergoing Analysis. References include Bugzilla and Mozilla security advisories. The vulnerability has a high CVSS score of 9.8, indicating critical severity. There is currently limited information available about potential exploits or attacks in the wild.
Official resources
AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-21T13:17:03.693Z and has not been modified since then. The NVD entry is currently Undergoing Analysis.