Medium (5.9) in mozilla. EPSS 6.2% chance of exploitation in the next 30 days.
A possible vulnerability exists where type confusion can occur when manipulating JavaScript objects in object groups, allowing for the bypassing of security checks within these groups. *Note: this vulnerability has only been demonstrated with UnboxedObjects, which are disabled by default on all supported releases.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.
Severity
CVSS 3.0
5.9 medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
6.2% chance of exploitation in the next 30 days; higher than 93% of CVEs (scores of 2026-10-31)