Predator and CL could not provide any possible suspects.
Using Code Search for the file, "NodeTraversal.h" assigning to the concern owner who might be related.

@yosin -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Thank You.

Mark Available to someone can pick this up.

It seems PositionIterator failed to handle SELECT.

Automatically applying components based on information from OWNERS files. If this seems incorrect, please apply the Test-Predator-Wrong-Components label.

Lower to Pri-3 since it is caused by unusual SELECT element markup.

ClusterFuzz has detected this issue as fixed in range 510178:510268.

Detailed report: https://clusterfuzz.com/testcase?key=5213663077335040

Fuzzer: ochang_domfuzzer
Job Type: windows_asan_content_shell
Platform Id: windows

Crash Type: Null-dereference READ
Crash Address: 0x00000008
Crash State:
  blink::NodeTraversal::ChildAtTemplate<const
  blink::PositionIteratorAlgorithm<blink::EditingAlgorithm<blink::NodeTraversal>
  blink::PositionIteratorAlgorithm<blink::EditingAlgorithm<blink::NodeTraversal>
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=windows_asan_content_shell&range=471041:471079
Fixed: https://clusterfuzz.com/revisions?job=windows_asan_content_shell&range=510178:510268

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5213663077335040

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.

ClusterFuzz testcase 5213663077335040 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.