The ShutdownObserver() was susceptible to potentially undefined behavior due to its reliance on a dynamic type that lacked a virtual destructor. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.
ShutdownObserver()
"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-6863.json"