| # Fastavro Avro Schema Traversal Crash | |
| Benign local PoC for fastavro `load_schema` handling of referenced `.avsc` schemas. | |
| Run: | |
| ```bash | |
| reproduce.py | |
| ``` | |
| Expected success tokens: | |
| ```text | |
| MFV_FASTAVRO_TRAVERSAL_MARKER_CONFIRMED | |
| MFV_FASTAVRO_SIGSEGV_CONFIRMED | |
| MFV_REPRO_OK_MFV-46 | |
| ``` | |
| The PoC uses only local schema files, subprocess isolation for the crashing case, and inert string markers. It does not use shell commands, network, secrets, persistence, or destructive file operations. | |