This is a serious security regression. If you are not able to fix this quickly, please revert the change that introduced it.

If this doesn't affect a release branch, or has not been properly classified for severity, please update the Security_Impact or Security_Severity labels, and remove the ReleaseBlock label. To disable this altogether, apply ReleaseBlock-NA.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

I'm guessing this is the v8 roll in the regression range, since there didn't seem to be any other suspicious changes.  Feel free to assign back to me if that is not the case.  Thanks !!!

The V8 roll doesn't contain anything suspicious either: https://chromium.googlesource.com/v8/v8/+log/45ad6a02..43bd6d3f

Also, while there is V8 further down on the stack, the top handful of frames is not in V8, which makes it unlikely that this is a V8 issue.

mlippautz, you've been in the scriptwrappable code recently (cd39e5b0ea), could you take a look?

Presumably this is related to  issue 753293  which showed up at the same time. 

I will check back and see if it also fixes this issue.

Kicked off another task on CF after fixing  issue 753293  to check whether it also fixed this one.

ClusterFuzz has detected this issue as fixed in range 493198:493237.

Detailed report: https://clusterfuzz.com/testcase?key=6723998762401792

Fuzzer: inferno_twister
Job Type: windows_syzyasan_content_shell
Platform Id: windows

Crash Type: Wild-access READ 4
Crash Address: 0x20646973
Crash State:
  blink::EventTarget::TraceWrappers
  blink::ScriptWrappableVisitor::DispatchTraceWrappers
  blink::TraceTrait<blink::PushEvent>::TraceMarkedWrapper
  
Memory Tool: SYZYASAN

Regressed: https://clusterfuzz.com/revisions?job=windows_syzyasan_content_shell&range=491650:491661
Fixed: https://clusterfuzz.com/revisions?job=windows_syzyasan_content_shell&range=493198:493237

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6723998762401792

See https://github.com/google/clusterfuzz-tools for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

This bug has been closed for more than 14 weeks. Removing security view restrictions.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot