Possible suspect from code search on file "j2k.c".
https://pdfium.googlesource.com/pdfium.git/+/e13ad88925bde037f4ed3b60f9ea5f01b883aa6e
npm@: Would you mind taking a look into this issue if its related to your change.

Currently its Impacting Stable (56.0.2924.87) & Beta (57.0.2987.88).

ClusterFuzz has detected this issue as fixed in range 470448:470475.

Detailed report: https://clusterfuzz.com/testcase?key=4863926996303872

Fuzzer: libfuzzer_pdf_jpx_fuzzer
Job Type: libfuzzer_chrome_ubsan
Platform Id: linux

Crash Type: Undefined-shift
Crash Address: 
Crash State:
  opj_tcd_dc_level_shift_decode
  opj_tcd_decode_tile
  opj_j2k_decode_tile
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_ubsan&range=395640:395746
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_ubsan&range=470448:470475

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=4863926996303872


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.

ClusterFuzz testcase 4863926996303872 is verified as fixed, so closing issue.

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

Fixed by https://pdfium.googlesource.com/pdfium/+/fe5c7c28c2f048eda4aa58cb8932d0d6f3f98114