---
tags:
  - security
  - proof-of-concept
  - tfrecords
license: mit
---

# TFRecords Example bytes_list materialization DoS PoC

This repository contains a benign security research PoC for a `.tfrecords`
artifact that drives large protobuf materialization during
`tf.train.Example.FromString(...)`.

Files:

- `control_same_size.tfrecords`
- `malicious_example_byteslist_10000000.tfrecords`
- `reproduce.py`

Observed behavior:

- control artifact:
  - parses successfully with one `bytes_list` item
- malicious artifact:
  - same size as control
  - parses successfully with `10,000,000` `bytes_list` items
  - materially increases peak RSS during normal parse

Reproduction:

```bash
python -m venv /tmp/tfrecord-byteslist-poc-venv
. /tmp/tfrecord-byteslist-poc-venv/bin/activate
pip install 'numpy<2' 'tensorflow==2.19.0'

TF_PYTHON_BIN="$(which python)" python3 build_poc.py
TF_PYTHON_BIN="$(which python)" python3 reproduce.py
```