Firefox MCallGetProperty Write Side Effects Use-After-Free Exploit

This Metasploit modules exploits CVE-2020-26950, a use-after-free exploit in Firefox. The MCallGetProperty opcode can be emitted with unmet assumptions resulting in an exploitable use-after-free condition. This exploit uses a somewhat novel technique of spraying ArgumentsData structures in order ...

JITSploitation III: Subverting Control Flow

Posted by Samuel Groß, Project Zero This three-part series highlights the technical challenges involved in finding and exploiting JavaScript engine vulnerabilities in modern web browsers and evaluates current exploit mitigation technologies. The exploited vulnerability, CVE-2020-9802, was fixed i...

JSC Exploits

Posted by Samuel Groß, Project Zero In this post, we will take a look at the WebKit exploits used to gain an initial foothold onto the iOS device and stage the privilege escalation exploits. All exploits here achieve shellcode execution inside the sandboxed renderer process WebContent on iOS...

Safari Proxy Object Type Confusion

This module exploits a type confusion bug in the Javascript Proxy object in WebKit. The DFG JIT does not take into account that, through the use of a Proxy, it is possible to run arbitrary JS code during the execution of a CreateThis operation. This makes it possible to change the structure of e....