Looks like it's hanging waiting for a response from venti; are you able to connect to venti directly? Did your venti or fossil config change recently? I'm not aware of recent changes to upstream venti that could cause this, but it's certainly possible, and venti and fossil are both fragile enough that i can imagine recent libc changes breaking them.

This also explains why Ori and Cinap experienced no issues, since their tests did not involve venti connections.