JavaScriptCore GetterSetter Type Confusion

JSC: GetterSetter type confusion during DFG compilation The following JavaScript program, found by Fuzzilli and slightly modified, crashes JavaScriptCore built from HEAD and the current stable release /System/Library/Frameworks/JavaScriptCore.framework/Resources/jsc: let notAGetterSetter =...

macOS iOS JavaScriptCore - JSValue Use-After-Free in ValueProfiles

macOS iOS JavaScriptCore - JSValue Use-After-Free in ValueProfiles While fuzzing JSC, I encountered the following JS program which crashes JSC from current HEAD and release /System/Library/Frameworks/JavaScriptCore.framework/Resources/jsc: // Run with --useConcurrentJIT=false...

Safari Webkit Proxy Object Type Confusion Exploit

This Metasploit 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...