Microsoft Chakra asm.js ArrayBuffer Use-After-Free Remote Code Execution Vulnerability

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Chakra. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the handling of...

Microsoft Edge Chakra CFG Bypass With leafInterpreterFrame Vulnerability

Chakra suffers from a CFG bypass with leafInterpreterFrame. Every JavaScript variable in Chakra except a tagged int is a pointer. From this pointer, using an arbitrary read, it is possible to follow a chain of pointers and end up with a pointer to the native stack. This allows disclosing the stac...

Microsoft Edge Chakra CFG Bypass Due To Bug In ServerFreeAllocation Vulnerability

Charka suffers from a CFG bypass due to a bug in ServerFreeAllocation. Chakra: CFG bypass due to a bug in ServerFreeAllocation CVE-2017-11874 Chakra JIT server exposes a ServerFreeAllocation method that can be used to free an existing JIT allocation for example when the corresponding function get...

Microsoft Edge: Chakra: JIT: GlobOpt::OptTagChecks must consider IsLoopPrePass properly(CVE-2017-11840)

There's one more place that emits a BailOnNotObject opcode. Here's a snippet of GlobOpt::OptTagChecks. if valueType.CanBeTaggedValue && !valueType.HasBeenNumber && this-IsLoopPrePass || !this-currentBlock-loop ValueType newValueType = valueType.SetCanBeTaggedValuefalse; // Split out the tag check...

Microsoft Edge: Chakra: JIT: Incorrect function declaration scope(CVE-2017-11870)

In the following JavaScript code, both of the print calls must print out "undefined" because of "x" is a formal parameter. But the second print call prints out "function x ". This bug may lead to type confusion in JITed code. function fx printx; function x printx; The following code in...

Microsoft Edge: Chakra: JIT: BailOutOnTaggedValue bailouts can be generated for constant values(CVE-2017-11839)

In the Chakra's JIT compilation process, it stores variables' type information by basic block. function optb let o; if b // BASIC BLOCK a o = ; else // BASIC BLOCK b o = 1.1; // BASIC BLOCK c return o; For example, let's think the above code gets optimized. At the basic block a, the type of "o"...

Microsoft Edge: Chakra: JIT: Inline::InlineCallApplyTarget_Shared doesn't return the return instruction(CVE-2017-11841)

Here's a snippet of Inline::Optimize. FOREACHINSTREDITINGinstr, instrNext, func-mheadInstr switch instr-mopcode case Js::OpCode::Label: ... if instr-AsLabelInstr-misForInExit Assertthis-currentForInDepth != 0; // The PoC hits this this-currentForInDepth--; break; case...

Microsoft Edge Chakra JIT - BailOutOnTaggedValue Bailouts Type Confusion

Microsoft Edge Chakra JIT - BailOutOnTaggedValue Bailouts Type Confusion / Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364 1. In the Chakra's JIT compilation process, it stores variables' type information by basic block. function optb let o; if b // BASIC BLOCK a o = ; else...

Microsoft Edge Chakra JIT - 'GlobOpt::OptTagChecks' Must Consider IsLoopPrePass Properly

/ Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1365 Some background: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364 There's one more place that emits a BailOnNotObject opcode. Here's a snippet of GlobOpt::OptTagChecks. if valueType.CanBeTaggedValue &&...

Microsoft Edge Chakra JIT - Inline::InlineCallApplyTarget_Shared does not Return the return Instruction

Microsoft Edge Chakra JIT - Inline::InlineCallApplyTargetShared does not Return the return Instruction / Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1366 Here's a snippet of Inline::Optimize. FOREACHINSTREDITINGinstr, instrNext, func-mheadInstr switch instr-mopcode case...

Microsoft Edge Chakra JIT - 'BailOutOnTaggedValue' Bailouts Type Confusion

/ Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364 1. In the Chakra's JIT compilation process, it stores variables' type information by basic block. function optb let o; if b // BASIC BLOCK a o = ; else // BASIC BLOCK b o = 1.1; // BASIC BLOCK c return o; For example, let's...

Microsoft Edge Chakra JIT - Incorrect Function Declaration Scope

/ Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1367 In the following JavaScript code, both of the print calls must print out "undefined" because of "x" is a formal parameter. But the second print call prints out "function x ". This bug may lead to type confusion in JITed code...

Microsoft Edge Chakra JIT - 'Inline::InlineCallApplyTarget_Shared' does not Return the return Instruction

/ Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1366 Here's a snippet of Inline::Optimize. FOREACHINSTREDITINGinstr, instrNext, func-mheadInstr switch instr-mopcode case Js::OpCode::Label: ... if instr-AsLabelInstr-misForInExit Assertthis-currentForInDepth != 0; // The PoC hit...

Microsoft Edge Chakra JIT - GlobOpt::OptTagChecks Must Consider IsLoopPrePass Properly

Microsoft Edge Chakra JIT - GlobOpt::OptTagChecks Must Consider IsLoopPrePass Properly / Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1365 Some background: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364 There's one more place that emits a BailOnNotObject opcod...

Microsoft Edge Chakra JIT - Incorrect Function Declaration Scope

Microsoft Edge Chakra JIT - Incorrect Function Declaration Scope / Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1367 In the following JavaScript code, both of the print calls must print out "undefined" because of "x" is a formal parameter. But the second print call prints out...

Microsoft Edge Chakra JIT Incorrect Function Declaration Scope Exploit

Exploit for windows platform in category dos / poc Microsoft Edge: Chakra: JIT: Incorrect function declaration scope CVE-2017-11870 In the following JavaScript code, both of the print calls must print out "undefined" because of "x" is a formal parameter. But the second print call prints out...

Microsoft Edge Chakra JIT BailOutOnTaggedValue Bailouts Exploit

Exploit for windows platform in category dos / poc Microsoft Edge: Chakra: JIT: BailOutOnTaggedValue bailouts can be generated for constant values CVE-2017-11839 1. In the Chakra's JIT compilation process, it stores variables' type information by basic block. function optb let o; if b // BASIC...

Microsoft Edge Chakra JIT Inline::InlineCallApplyTarget_Shared Failed Return Exploit

Exploit for windows platform in category dos / poc Microsoft Edge: Chakra: JIT: Inline::InlineCallApplyTargetShared doesn't return the return instruction CVE-2017-11841 Here's a snippet of Inline::Optimize. FOREACHINSTREDITINGinstr, instrNext, func-mheadInstr switch instr-mopcode case...

Microsoft Edge Chakra JIT GlobOpt::OptTagChecks Property Consideration Exploit

Exploit for windows platform in category dos / poc Microsoft Edge: Chakra: JIT: GlobOpt::OptTagChecks must consider IsLoopPrePass properly CVE-2017-11840 Some background: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364 There's one more place that emits a BailOnNotObject opcode...

Microsoft Edge Chakra JIT GlobOpt::OptTagChecks Property Consideration

Microsoft Edge: Chakra: JIT: GlobOpt::OptTagChecks must consider IsLoopPrePass properly CVE-2017-11840 Some background: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364 There's one more place that emits a BailOnNotObject opcode. Here's a snippet of GlobOpt::OptTagChecks. if...