CVE-2023-28176: Mozilla Firefox

High severity, CVSS 8.8. EPSS: 0.7% chance of exploitation in the next 30 days.

Memory safety bugs present in Firefox 110 and Firefox ESR 102.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 111, Firefox ESR < 102.9, and Thunderbird < 102.9.

Affected products

• Mozilla Firefox: before 111.0 (fixed in 111.0)
• Mozilla Firefox ESR: before 102.9 (fixed in 102.9)
• Mozilla Thunderbird: before 102.9 (fixed in 102.9)

Published 2023-06-02. Last modified 2026-06-17.