CVE-2019-9813

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 66.0.1 Firefox ESR versions prior to 60.6.1 Thunderbird versions prior to 60.6.1

Description The issue is related to incorrect handling of proto mutations, which may lead to type confusion in IonMonkey JIT code. This can be leveraged for arbitrary memory read and write, potentially allowing a remote attacker to impact the confidentiality, integrity, and availability of protected information.

Recommendations For Firefox versions prior to 66.0.1, update to version 66.0.1 or later to resolve the issue. For Firefox ESR versions prior to 60.6.1, update to version 60.6.1 or later to resolve the issue. For Thunderbird versions prior to 60.6.1, update to version 60.6.1 or later to resolve the issue. As a temporary workaround, consider disabling the IonMonkey JIT compiler until a patch is available.