Type Confusion in Mozilla Firefox and Firefox ESR - CVE-2020-15656

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 JIT optimizations involving the Javascript arguments object could confuse later optimizations in IonMonkey. A remote attacker can pass specially crafted data to the application, 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-2020-15656

Sources

• https://www.mozilla.org/en-US/security/advisories/mfsa2020-30/
• https://www.mozilla.org/en-US/security/advisories/mfsa2020-32/