danakj@  could you please look into this.please feel free to re-assigned back if needed. thanks in advance !

Can you look for a likely candidate in the regression range? Are you having trouble with that?

If there's nothing likely then the owners of blink::JSONParser would be appropriate. https://cs.chromium.org/chromium/src/third_party/WebKit/Source/platform/json/OWNERS?sq=package:chromium&type=cs

whesse@ could you please help me to find the culprit here. Thanks in advance 

I have nothing to do with blink or chromium.  I used to work on V8 5 years ago.

ClusterFuzz has detected this issue as fixed in range 426966:426989.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5729690365198336

Fuzzer: libfuzzer_blink_json_parser_fuzzer
Job Type: libfuzzer_chrome_ubsan
Platform Id: linux

Crash Type: Undefined-shift
Crash Address: 
Crash State:
  double WTF::toDoubleType<unsigned char,
  std::__1::unique_ptr<blink::JSONValue, std::__1::default_delete<blink::JSONValue
  std::__1::unique_ptr<blink::JSONValue, std::__1::default_delete<blink::JSONValue
  
Regressed: https://cluster-fuzz.appspot.com/revisions?job=libfuzzer_chrome_ubsan&range=423338:423416
Fixed: https://cluster-fuzz.appspot.com/revisions?job=libfuzzer_chrome_ubsan&range=426966:426989

Minimized Testcase (0.00 Kb):
Download: https://cluster-fuzz.appspot.com/download/AMIfv96UY1_ylFYvcthoI75OmnuPYGFcGPKPC_4a8smGVGp2Fsxhn5Y6AKbFx4Ge0U74zhrmbmzNeT_AUpW7YycUCY_kIQX9yoxFD0UvrnUdhaTe1AHjStfAXTkxajds3E2tcaowHP9mXJRd9te5CII3FNQsIrAvPw?testcase_id=5729690365198336
2E51


See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reproducing.md for more information.

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

Removing EditIssue view restrictions from ClusterFuzz filed bugs. If you believe that this issue should still be restricted, please reapply the label.

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