Predator and CL could not provide any possible suspects.

Using Code Search for the file, "url_canon_icu.cc" and observed some recent changes for the below file.

Suspect CL: https://chromium.googlesource.com/chromium/src/+/c5698b5c9d00bc9f9e9960995f6def95c714a41d%5E%21/url/url_canon_icu.cc

jshin@ -- Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.

Thanks!

 Issue 819749  has been merged into this issue.

This is not a regression. See https://chromium-review.googlesource.com/871350 for an example of fix. 

horo@ : can you make a CL similar to the one in comment 3?  Thank you 

Well, ksakamoto@ added a fuzzer. So, it'd be fairer to ask him :-). 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a65aaad7f9281737a9c3a2f55241436e351003f3

commit a65aaad7f9281737a9c3a2f55241436e351003f3
Author: Kunihiko Sakamoto <ksakamoto@chromium.org>
Date: Mon Mar 12 07:14:17 2018

Initialize ICU in SignedExchangeHeaderParser fuzzer

ICU needs to be initialized explicitly, because Signature header parsing
involves URL parsing which relies on ICU for IDN handling.

Bug:  819896 
Change-Id: Ia2c63e34eed78a586c7b471eec9b78ac9fbcb953
Reviewed-on: https://chromium-review.googlesource.com/958782
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Reviewed-by: Abhishek Arya <inferno@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Kunihiko Sakamoto <ksakamoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542436}
[modify] https://crrev.com/a65aaad7f9281737a9c3a2f55241436e351003f3/content/test/fuzzer/BUILD.gn
[modify] https://crrev.com/a65aaad7f9281737a9c3a2f55241436e351003f3/content/test/fuzzer/signed_exchange_header_parser_fuzzer.cc

ClusterFuzz has detected this issue as fixed in range 542431:542437.

Detailed report: https://clusterfuzz.com/testcase?key=6238453101232128

Fuzzer: libFuzzer_signed_exchange_header_parser_fuzzer
Job Type: libfuzzer_chrome_ubsan
Platform Id: linux

Crash Type: CHECK failure
Crash Address: 
Crash State:
  false. failed to open UTS46 data with error: U_FILE_ACCESS_ERROR. If you see thi
  url::UIDNAWrapper::UIDNAWrapper
  base::LazyInstanceTraitsBase<>::New
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_ubsan&range=541421:541432
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_ubsan&range=542431:542437

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6238453101232128

See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reference.md 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 6238453101232128 is verified as fixed, so closing issue as verified.

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