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 in that process and forcing a log-in to a malicious Firefox Sync account. 


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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.


Vulnerable Systems:

Firefox ESR < 60.9

Firefox ESR < 68.1

Firefox < 69


CVE Information:



Disclosure Timeline:
Published Date:1/8/2020

Categories: News