rtpsession: TWCC derived stats calculation crashes when there's packet loss

I have a GStreamer pipeline that acts as a sender. I was experimenting with TWCC accuracy by simulating the network with netem, and I found that TWCC derived stats calculation crashed on a segmentation fault shortly after I changed my NIC's packet loss to 5%: sudo tc qdisc add dev lo root netem loss 5%

I was using the 1.18.3 GStreamer version, the segmentation fault is 100% reproducible. Following is the stack trace: