Predator and CL could not provide any possible suspects.
Using the code search for the file, “mediasession.cc” assigning to concern owner from GIT blame.

Suspecting Commit# https://webrtc.git.corp.google.com/src.git/+/80cfb527c6e38267cdbf27ebce6a32595c80f21e

deadbeef@ -- Could you please look into this issue, kindly reassign if it has nothing to do with your changes.
Thank You.

ClusterFuzz has detected this issue as fixed in range 512097:512110.

Detailed report: https://clusterfuzz.com/testcase?key=6752283433107456

Fuzzer: inferno_twister
Job Type: windows_asan_chrome
Platform Id: windows

Crash Type: Null-dereference WRITE
Crash Address: 0x00000000
Crash State:
  raise
  rtc::FatalMessage::~FatalMessage
  cricket::MediaSessionDescriptionFactory::AddAudioContentForAnswer
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=windows_asan_chrome&range=508970:508978
Fixed: https://clusterfuzz.com/revisions?job=windows_asan_chrome&range=512097:512110

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6752283433107456

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 6752283433107456 is verified as fixed, so closing issue as verified.

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