Firefox ESR < 60.9 Improper Input Validation Vulnerability
Given a compromised sandboxed content process due to a separate vulnerability, it is possible to escape that sandbox by loading accounts.firefox.com in that process and forcing a log-in to a malicious Firefox Sync account.
The information has been provided by Vendor
The original article can be found at:https://www.mozilla.org/security/advisories/mfsa2019-25/
Preference settings that disable the sandbox are then synchronized to the local machine and the compromised browser would restart without the sandbox if a crash is triggered. This vulnerability affects Firefox ESR < 60.9, Firefox ESR < 68.1, and Firefox < 69.
Firefox ESR < 60.9
Firefox ESR < 68.1
Firefox < 69