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

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

The following revision refers to this bug:
  https://pdfium.googlesource.com/pdfium/+/e9fcd8e242d6fa655ca5a576a3dde9abbda24b64

commit e9fcd8e242d6fa655ca5a576a3dde9abbda24b64
Author: Ryan Harrison <rharrison@chromium.org>
Date: Wed Aug 23 19:14:11 2017

Reduce FM2JS parser depth limit to avoid memory exhaustion

The current limit of 2000 is still causing occassional ASAN issues,
reducing to 1250.

BUG= chromium:757711 

Change-Id: Idb07f97b01230afabcceaa23b29495432193ec64
Reviewed-on: https://pdfium-review.googlesource.com/11750
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

[modify] https://crrev.com/e9fcd8e242d6fa655ca5a576a3dde9abbda24b64/xfa/fxfa/fm2js/cxfa_fmparser.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/98e11067c060a3d6b86ba5256071eb45eaa71476

commit 98e11067c060a3d6b86ba5256071eb45eaa71476
Author: pdfium-deps-roller@chromium.org <pdfium-deps-roller@chromium.org>
Date: Wed Aug 23 20:44:56 2017

Roll src/third_party/pdfium/ 978b1fabf..e9fcd8e24 (1 commit)

https://pdfium.googlesource.com/pdfium.git/+log/978b1fabff13..e9fcd8e242d6

$ git log 978b1fabf..e9fcd8e24 --date=short --no-merges --format='%ad %ae %s'
2017-08-23 rharrison Reduce FM2JS parser depth limit to avoid memory exhaustion

Created with:
  roll-dep src/third_party/pdfium
BUG= 757711 


Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls


TBR=dsinclair@chromium.org

Change-Id: I17787a3339bb58f609ec5d48b9fa0faf13699faf
Reviewed-on: https://chromium-review.googlesource.com/629696
Reviewed-by: <pdfium-deps-roller@chromium.org>
Commit-Queue: <pdfium-deps-roller@chromium.org>
Cr-Commit-Position: refs/heads/master@{#496798}
[modify] https://crrev.com/98e11067c060a3d6b86ba5256071eb45eaa71476/DEPS

ClusterFuzz has detected this issue as fixed in range 496738:496804.

Detailed report: https://clusterfuzz.com/testcase?key=4578541902757888

Fuzzer: libFuzzer_pdf_fm2js_fuzzer
Job Type: libfuzzer_chrome_asan_debug
Platform Id: linux

Crash Type: Stack-overflow
Crash Address: 0x7fff205fccf8
Crash State:
  CXFA_FMLexer::NextToken
  CXFA_FMParser::NextToken
  CXFA_FMParser::ParsePostExpression
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=438794:438815
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=496738:496804

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=4578541902757888

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 4578541902757888 is verified as fixed, so closing issue as verified.

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