CVE-2026-16352
A memory error in Firefox and Thunderbird’s Disability Access APIs lets attackers escape the browser sandbox. The flaw is a use‑after‑free that can be triggered without any user interaction. It was fixed in recent releases of both products.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
Firefox versions earlier than 153, ESR 115.38, or ESR 140.13, and Thunderbird versions earlier than 153 or ESR 140.13.
Real-world impact
An attacker could run arbitrary code with the same privileges as the user, potentially taking full control of the affected system.
Why this severity
The CVSS score of 9.8 reflects that the vulnerability requires no authentication, no user interaction, and gives an attacker complete control over confidentiality, integrity, and availability.
What to do about it
- 011. Update Firefox to version 153 or newer, or ESR 115.38 or newer, or ESR 140.13 or newer.
- 022. Update Thunderbird to version 153 or newer, or ESR 140.13 or newer.
- 033. Restart the browser.
NVD-referenced vendor advisory
Timeline
- Jul 21, 2026 · 12d agoPublishedDisclosed and added to the National Vulnerability Database.
- Jul 23, 2026 · 10d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.
- Jul 24, 2026 · 9d agoAdvisory updatedThe NVD record was last revised.
How it’s attacked
References & advisories
- bugzilla.mozilla.org/show_bug.cgipermissions required
- mozilla.org/security/advisories/mfsa202…vendor advisory
- mozilla.org/security/advisories/mfsa202…vendor advisory
- mozilla.org/security/advisories/mfsa202…vendor advisory
- mozilla.org/security/advisories/mfsa202…vendor advisory
- mozilla.org/security/advisories/mfsa202…vendor advisory