Predator did not provide any possible suspects.
Assigning to the concern owner from CL --
https://chromium.googlesource.com/chromium/src/+log/9ad9f6860b4d6a4ec7f7f975b2c99672e02d5d49..fd61327a91c26467fae63304cc1ee343405344e6?pretty=fuller&n=10000

Suspecting Commit#
https://chromium.googlesource.com/chromium/src/+/af5b63b8f7f30e4dcbada7d2b756c68fa49157a2

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

ClusterFuzz has detected this issue as fixed in range 502180:502208.

Detailed report: https://clusterfuzz.com/testcase?key=5763936313147392

Fuzzer: phoglund_webrtc_peerconnection
Job Type: mac_asan_chrome
Platform Id: mac

Crash Type: Null-dereference READ
Crash Address: 0x000000000000
Crash State:
  webrtc::WebRtcSession::UpdateSessionState
  webrtc::WebRtcSession::SetLocalDescription
  webrtc::PeerConnection::SetLocalDescription
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=mac_asan_chrome&range=466596:466601
Fixed: https://clusterfuzz.com/revisions?job=mac_asan_chrome&range=502180:502208

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5763936313147392

Additional requirements: Requires HTTP

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 5763936313147392 is verified as fixed, so closing issue as verified.

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