Type Confusion in Firefox ESR and Mozilla Firefox - CVE-2019-9813

Detailed vulnerability description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a type confusion error when handling proto mutations in IonMonkey JIT code. A remote attacker can create a specially crafted web page, trick the victim into visiting it, trigger a type confusion error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

How to mitigate CVE-2019-9813

Sources

• https://www.mozilla.org/en-US/security/advisories/mfsa2019-09/
• https://www.mozilla.org/en-US/security/advisories/mfsa2019-10/
• https://bugzilla.mozilla.org/show_bug.cgi?id=1538006