Predator and CL could not provide any possible suspects.
Using Code Search for the file, "cpdf_streamcontentparser.cpp" assigning to the concern owner who might be related or previously who might have worked on same file.

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

 Issue 756420  has been merged into this issue.

This was introduced with: https://pdfium-review.googlesource.com/c/pdfium/+/11115 it looks like AddImage can return nullptr which isn't taken into account here.

 Issue 757139  has been merged into this issue.

The following revision refers to this bug:
  https://pdfium.googlesource.com/pdfium/+/77d8317f2e6bb9c75d96390fdf843b86694ba6d2

commit 77d8317f2e6bb9c75d96390fdf843b86694ba6d2
Author: Dan Sinclair <dsinclair@chromium.org>
Date: Wed Aug 23 12:52:19 2017

Verify image returned from AddImage

The ::AddImage call can return a nullptr if there is no stream provided.
This CL adds the missing null check on the returned object when lookikng
at the image.

Bug:  chromium:756418 ,  chromium:753700 
Change-Id: I48032c0f421c8889827540ae91f404ef0f503bfe
Reviewed-on: https://pdfium-review.googlesource.com/11532
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

[modify] https://crrev.com/77d8317f2e6bb9c75d96390fdf843b86694ba6d2/core/fpdfapi/page/cpdf_streamcontentparser.cpp

ClusterFuzz has detected this issue as fixed in range 496693:496743.

Detailed report: https://clusterfuzz.com/testcase?key=6402833556701184

Fuzzer: anil_pdf_fuzzer
Job Type: linux_asan_pdfium
Platform Id: linux

Crash Type: Null-dereference READ
Crash Address: 0x000000000068
Crash State:
  CPDF_StreamContentParser::Parse
  CPDF_ContentParser::Continue
  CPDF_PageObjectHolder::ContinueParse
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_asan_pdfium&range=495051:495074
Fixed: https://clusterfuzz.com/revisions?job=linux_asan_pdfium&range=496693:496743

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6402833556701184

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 6402833556701184 is verified as fixed, so closing issue as verified.

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